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  Subjects -> ENGINEERING (Total: 2279 journals)
    - CHEMICAL ENGINEERING (191 journals)
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ENGINEERING (1203 journals)                  1 2 3 4 5 6 7 | Last

Showing 1 - 200 of 1205 Journals sorted alphabetically
3 Biotech     Open Access   (Followers: 7)
3D Research     Hybrid Journal   (Followers: 19)
AAPG Bulletin     Full-text available via subscription   (Followers: 5)
AASRI Procedia     Open Access   (Followers: 15)
Abstract and Applied Analysis     Open Access   (Followers: 3)
Aceh International Journal of Science and Technology     Open Access   (Followers: 2)
ACS Nano     Full-text available via subscription   (Followers: 222)
Acta Geotechnica     Hybrid Journal   (Followers: 7)
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 5)
Acta Polytechnica : Journal of Advanced Engineering     Open Access   (Followers: 2)
Acta Scientiarum. Technology     Open Access   (Followers: 3)
Acta Universitatis Cibiniensis. Technical Series     Open Access  
Active and Passive Electronic Components     Open Access   (Followers: 7)
Adaptive Behavior     Hybrid Journal   (Followers: 11)
Adıyaman Üniversitesi Mühendislik Bilimleri Dergisi     Open Access  
Adsorption     Hybrid Journal   (Followers: 4)
Advanced Engineering Forum     Full-text available via subscription   (Followers: 6)
Advanced Science     Open Access   (Followers: 4)
Advanced Science Focus     Free   (Followers: 3)
Advanced Science Letters     Full-text available via subscription   (Followers: 5)
Advanced Science, Engineering and Medicine     Partially Free   (Followers: 7)
Advanced Synthesis & Catalysis     Hybrid Journal   (Followers: 17)
Advances in Artificial Neural Systems     Open Access   (Followers: 4)
Advances in Calculus of Variations     Hybrid Journal   (Followers: 2)
Advances in Catalysis     Full-text available via subscription   (Followers: 5)
Advances in Complex Systems     Hybrid Journal   (Followers: 7)
Advances in Engineering Software     Hybrid Journal   (Followers: 25)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 14)
Advances in Fuzzy Systems     Open Access   (Followers: 5)
Advances in Geosciences (ADGEO)     Open Access   (Followers: 10)
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Advances in Operations Research     Open Access   (Followers: 11)
Advances in OptoElectronics     Open Access   (Followers: 5)
Advances in Physics Theories and Applications     Open Access   (Followers: 12)
Advances in Polymer Science     Hybrid Journal   (Followers: 40)
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Advances in Remote Sensing     Open Access   (Followers: 37)
Advances in Science and Research (ASR)     Open Access   (Followers: 6)
Aerobiologia     Hybrid Journal   (Followers: 1)
African Journal of Science, Technology, Innovation and Development     Hybrid Journal   (Followers: 4)
AIChE Journal     Hybrid Journal   (Followers: 29)
Ain Shams Engineering Journal     Open Access   (Followers: 5)
Akademik Platform Mühendislik ve Fen Bilimleri Dergisi     Open Access  
Alexandria Engineering Journal     Open Access   (Followers: 1)
AMB Express     Open Access   (Followers: 1)
American Journal of Applied Sciences     Open Access   (Followers: 28)
American Journal of Engineering and Applied Sciences     Open Access   (Followers: 11)
American Journal of Engineering Education     Open Access   (Followers: 9)
American Journal of Environmental Engineering     Open Access   (Followers: 16)
American Journal of Industrial and Business Management     Open Access   (Followers: 23)
Analele Universitatii Ovidius Constanta - Seria Chimie     Open Access  
Annals of Combinatorics     Hybrid Journal   (Followers: 3)
Annals of Pure and Applied Logic     Open Access   (Followers: 2)
Annals of Regional Science     Hybrid Journal   (Followers: 7)
Annals of Science     Hybrid Journal   (Followers: 7)
Applicable Algebra in Engineering, Communication and Computing     Hybrid Journal   (Followers: 2)
Applicable Analysis: An International Journal     Hybrid Journal   (Followers: 1)
Applied Catalysis A: General     Hybrid Journal   (Followers: 6)
Applied Catalysis B: Environmental     Hybrid Journal   (Followers: 9)
Applied Clay Science     Hybrid Journal   (Followers: 4)
Applied Computational Intelligence and Soft Computing     Open Access   (Followers: 12)
Applied Magnetic Resonance     Hybrid Journal   (Followers: 3)
Applied Nanoscience     Open Access   (Followers: 7)
Applied Network Science     Open Access  
Applied Numerical Mathematics     Hybrid Journal   (Followers: 5)
Applied Physics Research     Open Access   (Followers: 3)
Applied Sciences     Open Access   (Followers: 2)
Applied Spatial Analysis and Policy     Hybrid Journal   (Followers: 4)
Arabian Journal for Science and Engineering     Hybrid Journal   (Followers: 5)
Archives of Computational Methods in Engineering     Hybrid Journal   (Followers: 4)
Archives of Foundry Engineering     Open Access  
Archives of Thermodynamics     Open Access   (Followers: 7)
Arid Zone Journal of Engineering, Technology and Environment     Open Access  
Arkiv för Matematik     Hybrid Journal   (Followers: 1)
ASEE Prism     Full-text available via subscription   (Followers: 3)
Asian Engineering Review     Open Access  
Asian Journal of Applied Science and Engineering     Open Access   (Followers: 1)
Asian Journal of Applied Sciences     Open Access   (Followers: 2)
Asian Journal of Biotechnology     Open Access   (Followers: 8)
Asian Journal of Control     Hybrid Journal  
Asian Journal of Current Engineering & Maths     Open Access  
Asian Journal of Technology Innovation     Hybrid Journal   (Followers: 8)
Assembly Automation     Hybrid Journal   (Followers: 2)
at - Automatisierungstechnik     Hybrid Journal   (Followers: 1)
ATZagenda     Hybrid Journal  
ATZextra worldwide     Hybrid Journal  
Australasian Physical & Engineering Sciences in Medicine     Hybrid Journal   (Followers: 1)
Australian Journal of Multi-Disciplinary Engineering     Full-text available via subscription   (Followers: 2)
Autonomous Mental Development, IEEE Transactions on     Hybrid Journal   (Followers: 8)
Avances en Ciencias e Ingeniería     Open Access  
Balkan Region Conference on Engineering and Business Education     Open Access   (Followers: 1)
Bangladesh Journal of Scientific and Industrial Research     Open Access  
Basin Research     Hybrid Journal   (Followers: 3)
Batteries     Open Access   (Followers: 4)
Bautechnik     Hybrid Journal   (Followers: 1)
Bell Labs Technical Journal     Hybrid Journal   (Followers: 23)
Beni-Suef University Journal of Basic and Applied Sciences     Open Access   (Followers: 3)
BER : Manufacturing Survey : Full Survey     Full-text available via subscription   (Followers: 2)
BER : Motor Trade Survey     Full-text available via subscription   (Followers: 1)
BER : Retail Sector Survey     Full-text available via subscription   (Followers: 2)
BER : Retail Survey : Full Survey     Full-text available via subscription   (Followers: 2)
BER : Survey of Business Conditions in Manufacturing : An Executive Summary     Full-text available via subscription   (Followers: 3)
BER : Survey of Business Conditions in Retail : An Executive Summary     Full-text available via subscription   (Followers: 3)
Bharatiya Vaigyanik evam Audyogik Anusandhan Patrika (BVAAP)     Open Access   (Followers: 1)
Biofuels Engineering     Open Access  
Biointerphases     Open Access   (Followers: 1)
Biomaterials Science     Full-text available via subscription   (Followers: 9)
Biomedical Engineering     Hybrid Journal   (Followers: 16)
Biomedical Engineering and Computational Biology     Open Access   (Followers: 13)
Biomedical Engineering Letters     Hybrid Journal   (Followers: 5)
Biomedical Engineering, IEEE Reviews in     Full-text available via subscription   (Followers: 17)
Biomedical Engineering, IEEE Transactions on     Hybrid Journal   (Followers: 32)
Biomedical Engineering: Applications, Basis and Communications     Hybrid Journal   (Followers: 5)
Biomedical Microdevices     Hybrid Journal   (Followers: 8)
Biomedical Science and Engineering     Open Access   (Followers: 3)
Biomedizinische Technik - Biomedical Engineering     Hybrid Journal  
Biomicrofluidics     Open Access   (Followers: 4)
BioNanoMaterials     Hybrid Journal   (Followers: 2)
Biotechnology Progress     Hybrid Journal   (Followers: 39)
Boletin Cientifico Tecnico INIMET     Open Access  
Botswana Journal of Technology     Full-text available via subscription  
Boundary Value Problems     Open Access   (Followers: 1)
Brazilian Journal of Science and Technology     Open Access   (Followers: 2)
Broadcasting, IEEE Transactions on     Hybrid Journal   (Followers: 10)
Bulletin of Canadian Petroleum Geology     Full-text available via subscription   (Followers: 14)
Bulletin of Engineering Geology and the Environment     Hybrid Journal   (Followers: 3)
Bulletin of the Crimean Astrophysical Observatory     Hybrid Journal  
Cahiers, Droit, Sciences et Technologies     Open Access  
Calphad     Hybrid Journal  
Canadian Geotechnical Journal     Hybrid Journal   (Followers: 14)
Canadian Journal of Remote Sensing     Full-text available via subscription   (Followers: 41)
Case Studies in Engineering Failure Analysis     Open Access   (Followers: 7)
Case Studies in Thermal Engineering     Open Access   (Followers: 3)
Catalysis Communications     Hybrid Journal   (Followers: 6)
Catalysis Letters     Hybrid Journal   (Followers: 2)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 8)
Catalysis Science and Technology     Free   (Followers: 6)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 3)
Catalysis Today     Hybrid Journal   (Followers: 5)
CEAS Space Journal     Hybrid Journal  
Cellular and Molecular Neurobiology     Hybrid Journal   (Followers: 3)
Central European Journal of Engineering     Hybrid Journal   (Followers: 1)
CFD Letters     Open Access   (Followers: 6)
Chaos : An Interdisciplinary Journal of Nonlinear Science     Hybrid Journal   (Followers: 2)
Chaos, Solitons & Fractals     Hybrid Journal   (Followers: 3)
Chinese Journal of Catalysis     Full-text available via subscription   (Followers: 2)
Chinese Journal of Engineering     Open Access   (Followers: 2)
Chinese Science Bulletin     Open Access   (Followers: 1)
Ciencia e Ingenieria Neogranadina     Open Access  
Ciencia en su PC     Open Access   (Followers: 1)
Ciencias Holguin     Open Access   (Followers: 1)
CienciaUAT     Open Access  
Cientifica     Open Access  
CIRP Annals - Manufacturing Technology     Full-text available via subscription   (Followers: 11)
CIRP Journal of Manufacturing Science and Technology     Full-text available via subscription   (Followers: 14)
City, Culture and Society     Hybrid Journal   (Followers: 21)
Clay Minerals     Full-text available via subscription   (Followers: 9)
Clean Air Journal     Full-text available via subscription   (Followers: 2)
Coal Science and Technology     Full-text available via subscription   (Followers: 3)
Coastal Engineering     Hybrid Journal   (Followers: 11)
Coastal Engineering Journal     Hybrid Journal   (Followers: 4)
Coatings     Open Access   (Followers: 3)
Cogent Engineering     Open Access   (Followers: 2)
Cognitive Computation     Hybrid Journal   (Followers: 4)
Color Research & Application     Hybrid Journal   (Followers: 1)
COMBINATORICA     Hybrid Journal  
Combustion Theory and Modelling     Hybrid Journal   (Followers: 13)
Combustion, Explosion, and Shock Waves     Hybrid Journal   (Followers: 13)
Communications Engineer     Hybrid Journal   (Followers: 1)
Communications in Numerical Methods in Engineering     Hybrid Journal   (Followers: 2)
Components, Packaging and Manufacturing Technology, IEEE Transactions on     Hybrid Journal   (Followers: 25)
Composite Interfaces     Hybrid Journal   (Followers: 6)
Composite Structures     Hybrid Journal   (Followers: 256)
Composites Part A : Applied Science and Manufacturing     Hybrid Journal   (Followers: 181)
Composites Part B : Engineering     Hybrid Journal   (Followers: 227)
Composites Science and Technology     Hybrid Journal   (Followers: 169)
Comptes Rendus Mécanique     Full-text available via subscription   (Followers: 2)
Computation     Open Access  
Computational Geosciences     Hybrid Journal   (Followers: 13)
Computational Optimization and Applications     Hybrid Journal   (Followers: 7)
Computational Science and Discovery     Full-text available via subscription   (Followers: 2)
Computer Applications in Engineering Education     Hybrid Journal   (Followers: 6)
Computer Science and Engineering     Open Access   (Followers: 17)
Computers & Geosciences     Hybrid Journal   (Followers: 28)
Computers & Mathematics with Applications     Full-text available via subscription   (Followers: 5)
Computers and Electronics in Agriculture     Hybrid Journal   (Followers: 4)
Computers and Geotechnics     Hybrid Journal   (Followers: 10)
Computing and Visualization in Science     Hybrid Journal   (Followers: 5)
Computing in Science & Engineering     Full-text available via subscription   (Followers: 29)
Conciencia Tecnologica     Open Access  
Concurrent Engineering     Hybrid Journal   (Followers: 3)
Continuum Mechanics and Thermodynamics     Hybrid Journal   (Followers: 6)
Control and Dynamic Systems     Full-text available via subscription   (Followers: 8)
Control Engineering Practice     Hybrid Journal   (Followers: 41)
Control Theory and Informatics     Open Access   (Followers: 7)
Corrosion Science     Hybrid Journal   (Followers: 25)
CT&F Ciencia, Tecnologia y Futuro     Open Access  

        1 2 3 4 5 6 7 | Last

Journal Cover Applied Catalysis A: General
  [SJR: 1.234]   [H-I: 159]   [6 followers]  Follow
    
   Hybrid Journal Hybrid journal (It can contain Open Access articles)
   ISSN (Print) 0926-860X
   Published by Elsevier Homepage  [3034 journals]
  • New insights in evaluation of acid sites in micro-mesoporous zeolite-like
           materials using potentiometric titration method
    • Authors: Nataliya D. Shcherban; Svitlana M. Filonenko; Roman Yu. Barakov; Sergii A. Sergiienko; Kai Yu; Ivo Heinmaa; Ari Ivaska; Dmitry Yu. Murzin
      Pages: 34 - 42
      Abstract: Publication date: 5 August 2017
      Source:Applied Catalysis A: General, Volume 543
      Author(s): Nataliya D. Shcherban, Svitlana M. Filonenko, Roman Yu. Barakov, Sergii A. Sergiienko, Kai Yu, Ivo Heinmaa, Ari Ivaska, Dmitry Yu. Murzin
      Potentiometric titration was used to characterize the acid-base properties of micro-mesoporous zeolite-like materials obtained via dual template synthesis using sol-precursors of Beta zeolite and micellar templates. The obtained results were compared with other methods of acidity determination (ammonia TPD, pyridine ad(de)sorption). The acid sites with the strength comparable to Beta zeolite (lg K values 4.3–4.7) were found in low-crystalline and X-ray amorphous micro-mesoporous materials. The strongest acid sites were observed in conventional Beta zeolite and a low-crystalline (degree of crystallinity ca. 0.1) micro-mesoporous material prepared on its basis (lg K 4.3) in concentration of 450 and 100μmol/g, respectively. A change from acidic to alkaline reaction media in the second stage of micro-mesoporous materials preparation led to an increase of the acid sites concentration from 190 to 600μmol/g concomitant with formation of a high fraction of comparatively strong acid sites (lg K 4.7, 200μmol/g). A high content of acid sites in low-crystalline and X-ray amorphous samples was assigned to acidity of zeolite precursors rather than zeolite crystals.
      Graphical abstract image

      PubDate: 2017-06-21T17:06:01Z
      DOI: 10.1016/j.apcata.2017.05.039
      Issue No: Vol. 543 (2017)
       
  • Enhancement of palladium-catalyzed direct desulfurization by yttrium
           addition
    • Authors: Ali Mansouri; Natalia Semagina
      Pages: 43 - 50
      Abstract: Publication date: 5 August 2017
      Source:Applied Catalysis A: General, Volume 543
      Author(s): Ali Mansouri, Natalia Semagina
      Bimetallic Pd-Y nanoparticles were synthesized by yttrium precursor reduction on the surface of colloidal Pd seeds catalyzed by palladium hydride. The addition of yttrium improved the thermal stability of the Pd nanoparticles to agglomeration. The nanoparticles before and/or after deposition on alumina were characterized by TEM, XPS, STEM with elemental mapping, temperature-programmed reduction, CO chemisorption and CO-DRIFT spectroscopy. The supported catalysts were evaluated in hydrodesulfurization (HDS) of 4,6-dimethydibenzothiophene at 350°C and 1MPa. Yttrium addition did not alter the overall HDS rate but increased the direct desulfurization selectivity from 71% to 84% and suppressed cracking twice as much as monometallic Pd catalyst did. The study demonstrates that PdY structures could be a promising candidate for low-pressure HDS of refractory sulfur compounds.
      Graphical abstract image

      PubDate: 2017-06-21T17:06:01Z
      DOI: 10.1016/j.apcata.2017.06.016
      Issue No: Vol. 543 (2017)
       
  • Promotion on light olefins production through modulating the reaction
           pathways for n-pentane catalytic cracking over ZSM-5 based catalysts
    • Authors: Xu Hou; Yuan Qiu; Enxian Yuan; Fuqiang Li; Zaizheng Li; Shuang Ji; Zhenning Yang; Guozhu Liu; Xiangwen Zhang
      Pages: 51 - 60
      Abstract: Publication date: 5 August 2017
      Source:Applied Catalysis A: General, Volume 543
      Author(s): Xu Hou, Yuan Qiu, Enxian Yuan, Fuqiang Li, Zaizheng Li, Shuang Ji, Zhenning Yang, Guozhu Liu, Xiangwen Zhang
      Insights into reaction mechanism were vital to direct naphtha catalytic cracking process to produce light olefins. In order to reveal influences of reaction pathways modulation on light olefins production, Zr-ZSM-5, Ag-ZSM-5, and the regenerated HZSM-5 (ZSM-5(R2)) were prepared and employed in n-pentane catalytic cracking. It was found that light olefins yield obtained over Zr-ZSM-5, Ag-ZSM-5, and ZSM-5(R2) at 500°C was 58%, 81%, and 113% higher than that over the parent HZSM-5 (12.0%), respectively. Promotion on light olefins production caused by Zr-incorporation can be attributed to the enhancement of hydride transfer reactions increasing the utilization of Brønsted acid sites and the catalytic activity accompanied with the proximate stability compared to the parent HZSM-5. Different from Zr-ZSM-5, Ag-ZSM-5 and ZSM-5(R2) respectively introduced dehydrogenation cracking and redox cracking to n-pentane catalytic cracking, which selectively promoted the formation of light olefins and significantly enhanced n-pentane protolytic cracking. However, both Ag-ZSM-5 and ZSM-5(R2) went through a rapid deactivation at 550°C, which was probably due the selective enhancement of alkenes accelerating the side reactions to coke formation.
      Graphical abstract image

      PubDate: 2017-06-21T17:06:01Z
      DOI: 10.1016/j.apcata.2017.06.013
      Issue No: Vol. 543 (2017)
       
  • Promoting effects of Ce and Pt addition on the destructive performances of
           V2O5/γ-Al2O3 for catalytic combustion of benzene
    • Authors: Peng Yang; Jingrong Li; Zhen Cheng; Shufeng Zuo
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Peng Yang, Jingrong Li, Zhen Cheng, Shufeng Zuo
      In the present work, a commercial mesoporous γ-Al2O3 with large specific surface area, high mechanical strength and good thermal stability was employed as the support for preparing a series of V2O5/γ-Al2O3 materials with different loading amounts of V2O5. Ce and Pt were introduced in order to further promote the oxidative performances for catalytic combustion of benzene, a typical pollutant of various volatile organic compounds (VOCs) in industrial waste gases. To investigate the structure − catalytic property relationship, these catalytic materials were systematically characterized by the XRD, N2 adsorption/desorption, HRTEM, EDX, H2-TPR and in-situ TPSR techniques. The results showed that the introduction of 10%wt Ce and 0.3%wt Pt significantly improved the catalytic oxidative activity and CO2 selectivity of the V2O5/γ-Al2O3 catalysts for benzene combustion, due to the obvious enhanced redox property resulted from the metal–metal and metal-support interaction as well as the high dispersion of the active components on γ-Al2O3. Furthermore, the 0.3%Pt/10%Ce-10%V/γ-Al2O3 catalyst also represented good durability and resistance to water and Cl-poisoning during the long-time continuous reaction, implying that it deserved more attention and had good potential for industrial application.
      Graphical abstract image

      PubDate: 2017-05-28T08:51:52Z
      DOI: 10.1016/j.apcata.2017.05.016
      Issue No: Vol. 542 (2017)
       
  • Particle size effect in glucose oxidation with Pd/CB catalysts
    • Authors: Tommy Haynes; Vincent Dubois; Sophie Hermans
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Tommy Haynes, Vincent Dubois, Sophie Hermans
      Palladium nanoparticles supported on carbon black were synthesized by two different methods precipitation- reduction (PR) and urea-assisted sodium formate homogeneous deposition (HD). The catalysts were then submitted to thermal treatments at 573K, 873K and 1173K to produce catalysts with a wide range of particle sizes. The obtained catalysts were characterized by XPS, TEM CO chemisorption and TGA measurements and tested in the oxidative dehydrogenation of glucose to gluconic acid. It was found that catalysts with a palladium particles size of 7nm exhibit the highest activity. Above or below this particular value the oxidative dehydrogenation of glucose appeared less efficient.
      Graphical abstract image

      PubDate: 2017-05-28T08:51:52Z
      DOI: 10.1016/j.apcata.2017.05.008
      Issue No: Vol. 542 (2017)
       
  • Acid-catalyzed hydrolysis of conifer lignosulfonate in black liquor for
           the production of value-added chemicals
    • Authors: Guiyu Zhang; Yeqian Wen; Zhihua Liu; Songmei Zhang; Gang Li
      Pages: 1 - 9
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Guiyu Zhang, Yeqian Wen, Zhihua Liu, Songmei Zhang, Gang Li
      Commercial sodium lignosulfonate from conifer black liquor (RSL) was used in our study to investigate acid-catalyzed hydrolysis of lignosulfonate (LS) by inorganic acids in aqueous solution. Before the hydrolysis process, RSL was purified by alcohol-water solution. Combustion method and gel permeation chromatography (GPC) of the high performance liquid chromatography system (HPLC) were used to detect the purification efficiency. The results showed that methanol-water solution had better purification effect. In addition, for the purified RSL (PSL-M), 0.5mol/L NaOH solution was chosen as the best dissolving medium through the comparison of aggregation behaviors of PSL-M in deionized water and various concentrations of NaOH solutions. In the following acid-catalyzed hydrolysis process, the experimental results proved that the three kinds of inorganic acids (HCl, H2SO4 and H3PO4) could catalytically hydrolyze PSL-M to lower molecular weight fractions and other organic chemicals, but HCl had the best efficiency. Moreover, in 0.5mol/L NaOH solution, PSL-M (solid-liquid ratio, 50g/L) catalytically hydrolyzed by 0.68mol/L HCl at 50°C for 10min could produce 1.729g/kg isovanillic acid, 0.088g/kg vanillin, 0.007g/kg syringaldehyde, 0.056g/kg acetosyringone and 0.024g/kg acetovanillone respectively.
      Graphical abstract image

      PubDate: 2017-05-22T14:25:11Z
      DOI: 10.1016/j.apcata.2017.05.004
      Issue No: Vol. 542 (2017)
       
  • Mechanochemical versus co-precipitated synthesized lanthanum-doped layered
           materials for olefin oxidation
    • Authors: O.D. Pavel; R. Zăvoianu; R. Bîrjega; E. Angelescu; V.I. Pârvulescu
      Pages: 10 - 20
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): O.D. Pavel, R. Zăvoianu, R. Bîrjega, E. Angelescu, V.I. Pârvulescu
      Layered catalytic materials with a double hydroxide structure and Mg2+/(Al3+ +La3+) =3 (Al3+/La3+ molar ratio of 1) were prepared via co-precipitation and mechanochemical routes. In the second one, stoichiometric amounts of nitrates in mixture with Na2CO3 and NaOH were directly milled in a ceramic mortar under ambient conditions. XRD characterization confirmed the formation of hydrotalcite structure for the samples containing Mg and Al, and of mixtures of La2(CO3)2(OH)2 and poor crystallized Mg,Al-layered double hydroxides for the samples modified by La. Catalytic tests carried out in the oxidation of cyclohexene by hydrogen peroxide in acetonitrile shown that the presence of lanthanum enhances the activity of the MgAlLa catalyst compared to unmodified MgAl. For MgAl the reconstruction of the LDH structure is a fast process occuring even under the reaction conditions that is favorized by the replacement of CO3 2− by OH−. This in situ anion replacement allows an increase of the catalytic activity. The addition of La to MgAl eliminates the advantages induced by the reconstruction but preserves the system epoxidation activity. On the other hand, the presence of La generates catalysts with improved stability and recyclability. This behavior has been assigned to the cooperative participation of the different crystallographic phases.
      Graphical abstract image

      PubDate: 2017-05-22T14:25:11Z
      DOI: 10.1016/j.apcata.2017.05.012
      Issue No: Vol. 542 (2017)
       
  • Remarkable improvement of cycling Fenton process for catalytic degradation
           of phenol: Tuning of triggering effect
    • Authors: Jinxi Feng; Siyang Li; Yong Sheng; Ya Xiong; Shenyu Lan; Shuanghong Tian; Lingjun Kong; Chao Fan
      Pages: 21 - 27
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Jinxi Feng, Siyang Li, Yong Sheng, Ya Xiong, Shenyu Lan, Shuanghong Tian, Lingjun Kong, Chao Fan
      A kind of effective cyclic Fenton process was investigated, in which Fe species were reused as homogeneous catalysts after the acid dissolution of Fe-containing sludge. It was observed that the degradation of phenol was abruptly accelerated (i.e., triggering effect) after an induction phase of ca. 30min for non-first runs. The abrupt acceleration was attributed to the rapid reduction of Fe(III) by poly-phenol intermediates, such as 1,2-hydroquinone, 1,4-hydroquinone and 1,2,4-trihydroxybenzene. Specially, it was found that sludge carbon (SC) could not only improve the precipitation performance of Fe and Al species, decreasing residual concentration of Fe and Al species to 0.11mgL−1 and 4.6mgL−1, respectively, but also reduce considerably induction phase of the degradation, promoting the advent of the triggering effect in advance. The promotion of SC was stemmed from its unique co-catalytic property, by which Fe(III) was continuously reduced to active Fe(II) and H2O2 was turned to stronger oxidizing OH and 1O2.
      Graphical abstract image

      PubDate: 2017-05-22T14:25:11Z
      DOI: 10.1016/j.apcata.2017.05.009
      Issue No: Vol. 542 (2017)
       
  • Microwave synthesis of SAPO-11 materials for long chain n-alkanes
           hydroisomerization: Effect of physical parameters and chemical gel
           composition
    • Authors: R. Bértolo; J.M. Silva; M.F. Ribeiro; A. Martins; A. Fernandes
      Pages: 28 - 37
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): R. Bértolo, J.M. Silva, M.F. Ribeiro, A. Martins, A. Fernandes
      The present work concerns the preparation of SAPO-11 materials using microwave (MW) heating during the crystallization process. Different experimental conditions such as crystallization temperature and time were explored, together with different Si sources. The final materials were fully characterized using chemical analysis, XRD diffraction, pyridine adsorption followed by FTIR, nitrogen sorption and NMR spectroscopy and compared with the respective conventional SAPO-11 materials, synthesized using the same initial chemical composition of the gel but under conventional electric heating. The results showed that SAPO-11 materials can be synthesized in less time (within minutes) and at lower temperature (170°C) with MW heating than with conventional heating (respectively 24h and 200°C). MW heating allows nanosized SAPO-11 materials to be obtained but the nature of the Si source used has a marked influence on the textural properties and, especially, on the acidity of SAPO-11. The catalytic properties of the materials (with 0.5wt.% Pt) were evaluated in the hydroisomerization of long chain n-alkanes using n-decane as model molecule. Optimized MW samples using colloidal AS-40 Si source showed higher yields in monobranched isomers due to a joint effect of low acidity and suitable textural properties.
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      PubDate: 2017-05-22T14:25:11Z
      DOI: 10.1016/j.apcata.2017.05.010
      Issue No: Vol. 542 (2017)
       
  • DRIFT study on promotion effects of tungsten-modified Mn/Ce/Ti catalysts
           for the SCR reaction at low-temperature
    • Authors: Ki Bok Nam; Dong Wook Kwon; Sung Chang Hong
      Pages: 55 - 62
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Ki Bok Nam, Dong Wook Kwon, Sung Chang Hong
      The adsorption characteristics of the catalyst surface was studied using FT-IR (DRIFT) to determine the promotion and the causes as W is added through Mn/Ce/Ti and Mn/Ce/W/Ti catalysts. Addition of W to Mn/Ce/Ti catalyst promotes activity below 200°C. In the FT-IR performed DRIFT test, the Mn/Ce/W/Ti catalyst showed an excellent reaction activity at the SCR reaction when NH3 was introduced; also, compared with the Mn/Ce/Ti catalyst, the absorption-acid site of the NH3 increased with a NH4 + that adsorbed to the Brønsted-acid site. Afterward, when NO+O2 was introduced to cause a reaction with the adsorbed NH3, the NH3 adsorbed species quickly decreased at the Mn/Ce/W/Ti catalyst. Next, when the NO+O2 was initially adsorbed, monodentate nitrate, bidentate nitrate, and bridged nitrate adsorbed species were created on the surfaces of the Mn/Ce/W/Ti and Mn/Ce/Ti catalysts. When NH3 was introduced for the reaction, part of the bridged nitrate reacted, but the NO adsorbed species on the catalyst surface were generally less reactive. Therefore, the NO adsorbed on the catalyst surface exhibit a very low reaction activity as compared with the adsorbed NH3. The Mn/Ce/W/Ti catalyst with the W had the inhibited overall nitrate adsorbed species than the Mn/Ce/Ti catalyst. Therefore, the Mn/Ce/W/Ti catalysts increased the low-temperature SCR reaction activity by the increase of the ammonia adsorbent species having excellent reactivity and the decrease of the adsorption of the less reactive nitrogen oxide, compared with the Mn/Ce/Ti catalyst.
      Graphical abstract image

      PubDate: 2017-06-02T07:48:45Z
      DOI: 10.1016/j.apcata.2017.05.017
      Issue No: Vol. 542 (2017)
       
  • Chromium catalysts for selective ethylene oligomerization to 1-hexene and
           1-octene: Recent results
    • Authors: Kirill A. Alferov; Gennadiy P. Belov; Yuezhong Meng
      Pages: 71 - 124
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Kirill A. Alferov, Gennadiy P. Belov, Yuezhong Meng
      The objective of this review is the analysis and comment of recent publication results (from July 2010 until February 2017) obtained for selective ethylene oligomerization toward 1-hexene and 1-octene catalyzed by chromium-based catalytic systems. Both the scientific and patent literature was taken into the consideration. The catalytic systems for ethylene oligomerization are classified on the basis of the ligand type employed. The activities and selectivities of the catalysts are provided throughout the text. Despite a big success in the field, there is still rather limited choice of catalysts affording simultaneously high activity, selectivity and low polymer proportion. This is especially true for ethylene to 1-octene tetramerization reaction. The results of the studies concerning oligomerization mechanisms obtained over the recent years are also included in this review.
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      PubDate: 2017-06-02T07:48:45Z
      DOI: 10.1016/j.apcata.2017.05.014
      Issue No: Vol. 542 (2017)
       
  • Development and testing of an additively manufactured monolithic catalyst
           bed for HTP thruster applications
    • Authors: K. Essa; H. Hassanin; M.M. Attallah; N.J. Adkins; A.J. Musker; G.T. Roberts; N. Tenev; M. Smith
      Pages: 125 - 135
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): K. Essa, H. Hassanin, M.M. Attallah, N.J. Adkins, A.J. Musker, G.T. Roberts, N. Tenev, M. Smith
      Additive manufacturing (AM), also known as 3D printing, is a revolutionary manufacturing technology that has attracted many industries in the past two decades. This is because AM enables the manufacturing of complex-shaped geometries without the limitations of other manufacturing techniques. In this paper, the design, development and testing of additively manufactured, monolithic catalyst beds are described. A novel design methodology was employed and achieved catalyst bed designs with complex geometry and high geometrical surface area whilst achieving an acceptable pressure drop. Catalyst bed samples incorporating alumina ceramic lattices with strut diameters ranging from 0.15 to 0.30mm were fabricated via AM and a subsequent heat treatment. The surface areas of the samples were improved using different wash coats, including the use of gamma alumina and a mixture of gamma alumina and carbon nanotubes (CNT). Manganese oxides were used to coat the catalyst bed and decompose hydrogen peroxide. Four full-scale catalyst beds with the most promising candidate geometries and wash coats were then manufactured and subsequently tested in a 20 N-class HTP (High Test Peroxide) monopropellant thruster. The firing results show that the additively manufactured catalyst beds generally outperformed the baseline catalyst bed containing ceria pellets that were also coated with manganese oxides.
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      PubDate: 2017-06-02T07:48:45Z
      DOI: 10.1016/j.apcata.2017.05.019
      Issue No: Vol. 542 (2017)
       
  • Carbonate hydroxyapatite as a catalyst for ethanol conversion to
           hydrocarbon fuels
    • Authors: Juan J. Lovón-Quintana; Julie K. Rodriguez-Guerrero; P. Gustavo Valença
      Pages: 136 - 145
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Juan J. Lovón-Quintana, Julie K. Rodriguez-Guerrero, P. Gustavo Valença
      Carbonate hydroxyapatite (CHAP) was successfully used as a catalyst for direct ethanol conversion into hydrocarbon fuels in a single-step gas-phase reaction. The CHAP was synthesized by chemical precipitation method in basic media using an alkali-free system. After heat treatments, it was widely characterized by XRF, XRD, FTIR, XPS, pyridine-TPD, CO2 chemisorption, and N2 adsorption at −196°C. The physical-chemical analysis indicates the formation of B-type CHAP and the presence of acid and basic surface sites being able to act as a bifunctional catalyst. Under optimum conditions of reaction temperature (500°C) and modified residence time W/FEthanol (40ghmol−1), the ethanol conversion showed a high yield (≈97%) to a mixture of non-oxygenated and oxygenated hydrocarbon fuels with carbon chain lengths in the range from C4 to C18+. After condensation of the reaction products an oily and one aqueous phases were obtained. The net calorific value (NCV) of the oily phase (≈41.3MJkg−1) was close to those found in conventional fossil fuels.
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      PubDate: 2017-06-02T07:48:45Z
      DOI: 10.1016/j.apcata.2017.05.020
      Issue No: Vol. 542 (2017)
       
  • Reductive amination of isopropanol to monoisopropylamine over
           Ni-Fe/γ-Al2O3 catalysts: Synergetic effect of Ni-Fe alloy formation
    • Authors: Eunpyo Hong; Seonu Bang; Jun Hee Cho; Kwang Deog Jung; Chae-Ho Shin
      Pages: 146 - 153
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Eunpyo Hong, Seonu Bang, Jun Hee Cho, Kwang Deog Jung, Chae-Ho Shin
      We herein reported the syntheses of 17wt% Ni-xFe/γ-Al2O3 catalysts containing different Fe/Ni molar ratios (x=0–0.7) via an incipient wetness impregnation method, followed by subsequent investigation of their catalytic properties in the reductive amination of isopropanol (IPA). We attempted to reveal the synergetic effect of bimetallic Ni-Fe on γ-Al2O3 support through characterization of the catalysts by N2-sorption, X-ray diffraction, H2-temperature-programmed reduction, and X-ray photoelectron spectroscopy. We found that conversion and selectivity to monoisopropylamine (MIPA) through the reductive amination of IPA was influenced by the reducibility of the catalysts. In addition, the surface Ni0 content increased upon the addition of Fe species, with a maximum Ni0 content being reached at a Fe/Ni molar ratio of 0.3. This molar ratio also yielded the highest conversion and MIPA selectivity, and no deactivation was observed for 100h on stream in the presence of hydrogen gas. In addition, reaction parameters, such as the partial pressures of H2 and NH3, the space velocity, and the reaction temperature were also examined to optimize the experimental conditions.
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      PubDate: 2017-06-02T07:48:45Z
      DOI: 10.1016/j.apcata.2017.05.003
      Issue No: Vol. 542 (2017)
       
  • Effect of potassium promotion on the structure and performance of alumina
           supported carburized molybdenum catalysts for Fischer-Tropsch synthesis
    • Authors: Tong Li; Mirella Virginie; Andrei Y. Khodakov
      Pages: 154 - 162
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Tong Li, Mirella Virginie, Andrei Y. Khodakov
      Fischer-Tropsch synthesis produces light olefins and long chain hydrocarbons from syngas generated from fossil and renewable feedstocks. Molybdenum carbide exhibits catalytic properties approaching those of metal catalysts in a number of hydrogenation reactions. The present paper focuses on the effect of promotion with potassium on the structure and performance of alumina supported carburized molybdenum catalysts in Fischer-Tropsch synthesis. Molybdenum carbide catalysts were synthesized by temperature programmed carburization in methane and hydrogen. Molybdenum was highly dispersed in both calcined and carburized alumina supported catalysts. Mixed oxides of potassium, molybdenum and aluminium were uncovered in the calcined promoted catalysts. These oxides are converted in molybdenum carbide species on their carburization. Potassium promotion strengthens interaction between molybdenum and aluminium. The potassium promoted catalysts exhibited higher selectivity to light olefins and long chain hydrocarbons but lower Fischer-Tropsch reaction rate compared to the unpromoted counterpart. The observed lower Fischer-Tropsch reaction rate on the promoted catalysts was attributed to more difficult carburization of the molybdenum species and electronic effects due to the presence of potassium. The light olefin and C5+ selectivities decrease at higher carbon monoxide conversion probably because of secondary olefin hydrogenation and hydrocarbon hydrogenolysis.
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      PubDate: 2017-06-02T07:48:45Z
      DOI: 10.1016/j.apcata.2017.05.018
      Issue No: Vol. 542 (2017)
       
  • Liquid phase in situ hydrodeoxygenation of biomass-derived phenolic
           compounds to hydrocarbons over bifunctional catalysts
    • Authors: Junfeng Feng; Chung-yun Hse; Zhongzhi Yang; Kui Wang; Jianchun Jiang; Junming Xu
      Pages: 163 - 173
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Junfeng Feng, Chung-yun Hse, Zhongzhi Yang, Kui Wang, Jianchun Jiang, Junming Xu
      The objective of this study was to find an effective method for converting renewable biomass-derived phenolic compounds into hydrocarbons bio-fuel via in situ catalytic hydrodeoxygenation. The in situ hydrodeoxygenation of biomass-derived phenolic compounds was carried out in methanol-water solvent over bifunctional catalysts of Raney Ni and HZSM-5 or H-Beta. In the in situ hydrodeoxygenation, the hydrogen was donated by aqueous phase reforming of methanol without external hydrogen gas. This reaction pathway for liquid-phase in situ hydrodeoxygenation of phenolic monomers was based on methanol-water as a solvent, stepwise metal-catalyzed hydrogenation, acid-catalyzed dehydration, and metal-catalyzed hydrolysis. The three-step conversion process can be achieved by a one-pot procedure. When HZSM-5 (Si/Al ratio of 25) and Raney Ni were used as the bifunctional catalysts of in situ hydrodeoxygenation, more than 90% conversion of phenolic monomers and dimers, approximately 70–90% selectivity of cyclohexanes and hydrocarbons could be obtained at 220°C with a reaction time of 7h. The bifunctional catalysts combined Raney Ni with HZSM-5 can achieve the aqueous-phase reforming of methanol, which coupled with the in situ hydrodeoxygenation of phenolic compounds. Therefore, this in situ hydrodeoxygenation process with bifunctional catalysts provided an efficient route for upgrading bio-oil containing large amounts of phenolic compounds into renewable hydrocarbon products.
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      PubDate: 2017-06-07T07:13:21Z
      DOI: 10.1016/j.apcata.2017.05.022
      Issue No: Vol. 542 (2017)
       
  • Synthesis of glycerol carbonate from glycerol and dimethyl carbonate
           catalyzed by calcined silicates
    • Authors: Song Wang; Pengfei Hao; Sanxi Li; Ailing Zhang; Yinyan Guan; Linnan Zhang
      Pages: 174 - 181
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Song Wang, Pengfei Hao, Sanxi Li, Ailing Zhang, Yinyan Guan, Linnan Zhang
      Several anhydrous silicates were prepared by calcination at 400°C and utilized as solid base catalyst for synthesizing glycerol carbonate (GC) by transesterification of glycerol with dimethyl carbonate (DMC). Among them, calcined sodium silicate showed the best catalytic activity with glycerol conversion of 97.7%. Then, a series of sodium silicates calcined at different temperatures were characterized using TGA, Hammett indicator method, BET, XRD, FT-IR and FESEM. Effect of calcination temperature on their catalytic ability was carefully investigated, followed by a reaction optimization study. The basicity of sodium silicates calcined at different temperatures highly depended on calcination temperature; their catalytic ability was affected by their total basicity rather than by their BET surface area; and the increased amount of strong basic sites resulted in the formation of by-product which decreased the GC yield and GC selectivity. Sodium silicate calcined at 200°C (Na2SiO3-200), which had the intermediate total basicity and relative low amount of strong basic sites, incurred the highest GC yield. The highest catalytic performance of Na2SiO3-200 was achieved under the condition that the 4:1 molar ratio of DMC to glycerol was reacted at 75°C for 2.5h. This catalyst could be reused five times without noticeable drop in catalytic activity.
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      PubDate: 2017-06-07T07:13:21Z
      DOI: 10.1016/j.apcata.2017.05.021
      Issue No: Vol. 542 (2017)
       
  • Highly selective immobilized bimetallic Ni-Au nanoparticle catalyst for
           the partial hydrogenation of m-dinitrobenzene
    • Authors: Daniel Lamey; Oliver Beswick; Fernando Cárdenas-Lizana; Paul J. Dyson; Esther Sulman; Lioubov Kiwi-Minsker
      Pages: 182 - 190
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Daniel Lamey, Oliver Beswick, Fernando Cárdenas-Lizana, Paul J. Dyson, Esther Sulman, Lioubov Kiwi-Minsker
      Transition metal nanoparticles (NPs) are extensively used as catalysts for a wide and diverse range of organic transformations when immobilized on appropriate solid supports. We describe the development of a highly active and highly selective heterogeneous catalyst based on Ni-Au NPs supported on activated carbon fibers (ACFs) for the partial reduction of m-dinitrobenzene (m-DNB) to m-nitroaniline (m-NAN), an important platform chemical used in the synthesis of dyes and polymers. Initially, Ni NPs with narrow size distribution and ranging from 2 to 14nm were prepared with poly-N-vinyl-2-pyrrolidone (PVP) as a stabilizer. Evaluation of the NPs as catalysts in the liquid-phase hydrogenation of m-dinitrobenzene led to the establishment of an antipathetic structure sensitivity, i.e. the larger NPs displayed a 6-fold higher turnover frequency than the smaller NPs. The selectivity to the target m-NAN product is independent of the size of the Ni NPs, possibly due to preferential PVP absorption of the NP edges and vertices. Consequently, Ni NPs of 2nm were supported on ACFs and residual PVP was removed by a ultra-violet ozone (UVO) treatment, rendering a highly selective structured catalyst that affords m-NAN in almost 96% yield. A two-site (plane vs. edge Ni-atoms) Langmuir–Hinshelwood kinetic model is consistent with the experimental kinetic data confirming that low-coordination atoms (edges and vertices) are responsible for selective reaction. Consequently, we prepared bimetallic Ni-Au NPs (Ni:Au=1:1) aiming to generate Ni surface sites mimicking the properties of edge and vertex atoms. The resulting UVO-treated Ni-Au NPs of 3nm immobilized on ACFs afford m-NAN with a yield exceeding 98%. Such a high yield appears to be unprecedented and shows how careful nanocatalyst design, guided by detailed structural characterization and mechanistic studied, can lead to highly selective catalysts of industrial relevance.
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      PubDate: 2017-06-07T07:13:21Z
      DOI: 10.1016/j.apcata.2017.05.015
      Issue No: Vol. 542 (2017)
       
  • Metallophthalocyanine intercalated layered double hydroxides as an
           efficient catalyst for the selective epoxidation of olefin with oxygen
    • Authors: Weiyou Zhou; Jiacheng Zhou; Yong Chen; Aijun Cui; Fu’an Sun; Mingyang He; Zhixiang Xu; Qun Chen
      Pages: 191 - 200
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Weiyou Zhou, Jiacheng Zhou, Yong Chen, Aijun Cui, Fu’an Sun, Mingyang He, Zhixiang Xu, Qun Chen
      Varied metallophthalocyanine intercalated layered double hydroxides (LDHs) as bifunctional hybrid catalysts for selective epoxidation have been prepared and characterized. Systematic characterizations suggested the successful intercalation of the metallophthalocyanines into the interlayer of ZnAl LDHs. The synthesized hybrid exhibited excellent catalytic activity in the selective epoxidation of various olefins through O2/isobutaldehyde system. The basicity of the hybrid benefits to the selectivity of epoxide, and the bifunctional roles of the catalyst in the reaction have been discussed and verified by a series of controlled experiments. On the basis of obtained results, a probable mechanism of the epoxidation by the hybrid has been proposed and detailedly investigated. Under the catalysis of metallophthalocyanines intercalated LDHs in the presence of O2/isobutaldehyde, the production of epoxide undergoes two reaction paths. And two types of intermediates, namely acylperoxy radical and peroxyacid, are formed in the reaction, and the former is predominant.
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      PubDate: 2017-06-07T07:13:21Z
      DOI: 10.1016/j.apcata.2017.05.029
      Issue No: Vol. 542 (2017)
       
  • Glycerol steam reforming over modified Ru/Al2O3 catalysts
    • Authors: K. Kousi; D.I. Kondarides; X.E. Verykios; C. Papadopoulou
      Pages: 201 - 211
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): K. Kousi, D.I. Kondarides, X.E. Verykios, C. Papadopoulou
      Glycerol, a by-product of biodiesel industry, could be utilized for the production of hydrogen via steam reforming. In the present work, three Ru-based catalysts, namely Ru/Al2O3, Ru/Β2Ο3-Al2O3 and Ru/MgO-Al2O3, have been studied regarding their physicochemical and catalytic properties for the title reaction. N2 adsorption-desorption, powder XRD, CO Adsorption, NH3-TPD, CO2-TPD, TPR, TEM and SEM-EDS were employed to investigate the textural and structural characteristics of the catalysts. Quantitative assessment of the carbonaceous deposits, formed under reaction conditions, was performed using TPH and TPO methods The catalytic performance of the synthesized catalysts for the glycerol steam reforming reaction has been investigated in a fixed bed plug flow reactor using a feed of water/glycerol at a molar ratio of 20:1 at 400, 500 and 600°C. Results show that at the low reaction temperature (400°C), the support has a determining role on the catalytic performance, the selectivity to various oxygenates depending on the acid-base properties of the catalyst. At higher temperature (600°C) metal activity dominates, H2 and CO2 being the main reaction products.
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      PubDate: 2017-06-12T04:50:30Z
      DOI: 10.1016/j.apcata.2017.05.027
      Issue No: Vol. 542 (2017)
       
  • Gas phase synthesis of isopropyl chloride from isopropanol and HCl over
           alumina and flexible 3-D carbon foam supported catalysts
    • Authors: Natalia Bukhanko; Christopher Schwarz; Ajaikumar Samikannu; Tung Ngoc Pham; William Siljebo; Johan Wärnå; Andrey Shchukarev; Anne-Riikka Rautio; Krisztian Kordás; Jyri-Pekka Mikkola
      Pages: 212 - 225
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Natalia Bukhanko, Christopher Schwarz, Ajaikumar Samikannu, Tung Ngoc Pham, William Siljebo, Johan Wärnå, Andrey Shchukarev, Anne-Riikka Rautio, Krisztian Kordás, Jyri-Pekka Mikkola
      Isopropyl chloride synthesis from isopropanol and HCl in gas phase over ZnCl2 catalysts supported on Al2O3 as well as flexible carbon foam was studied in a continuous reactor. A series of catalytic materials were synthesised and characterised by BET, XPS, SEM, TEM, XRD and NH3-TPD methods. Catalytic activity tests (product selectivity and conversion of reactants) were performed for all materials and optimal reaction conditions (temperature and feedstock flow rates) were found. The results indicate that the highest yield of isopropyl chloride was obtained over 5wt.% ZnCl2 on commercial Al2O3 (No. II) (95.3%). Determination of product mixture compositions and by-product identification were done using a GC-MS method. Carbon foam variant catalyst, 5wt.% ZnCl2/C, was found to perform best out of the carbon-supported materials, achieving ∼75% yield of isopropyl chloride. The kinetic model describing the process in a continuous packed bed reactor was proposed and kinetic parameters were calculated. The activation energy for the formation of isopropyl chloride reaction directly from isopropanol and HCl was found to be ∼58kJ/mol.
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      PubDate: 2017-06-12T04:50:30Z
      DOI: 10.1016/j.apcata.2017.05.013
      Issue No: Vol. 542 (2017)
       
  • Identifying the nature of the copper entities over ceria-based supports to
           promote diesel soot combustion: Synergistic effects
    • Authors: Javier Giménez-Mañogil; Avelina García-García
      Pages: 226 - 239
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Javier Giménez-Mañogil, Avelina García-García
      The aim of this research is to prepare catalysts exhibiting a wide range of copper incorporation/distribution/contact degrees on ceria-zirconia mixed oxide by preparing catalysts with a high degree of copper incorporation, well-dispersed copper on the surface/porosity and different degrees of physical interaction. Their catalytic activities towards diesel soot combustion and NO oxidation to NO2 were analyzed with the purpose to identify the nature of the copper entities over ceria-based supports to promote diesel soot combustion. The catalysts were characterized by N2 adsorption-desorption isotherms at −196°C, XRD, Raman spectroscopy, XPS, H2-TPR and reducibility tests under inert atmosphere. Activity tests were performed towards NO oxidation to NO2 (from 25°C to 700°C) and diesel soot combustion in NOx/O2 atmosphere, under ramp mode (from 25°C to 700°C) and isothermal conditions (450°C). Results reveal that copper in close contact with ceria greatly promotes its reducibility under H2 and He at low temperatures, as well as catalytic NO oxidation to NO2. Mainly, 2%Cu/ceria-zirconia catalyst prepared by incipient wetness impregnation shows the highest activity towards soot combustion at low temperatures (≤450°C), due to the observed synergistic copper-ceria interactions.
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      PubDate: 2017-06-12T04:50:30Z
      DOI: 10.1016/j.apcata.2017.05.031
      Issue No: Vol. 542 (2017)
       
  • Acid pretreatment effect on the physicochemical property and catalytic
           performance of CeO2 for NH3-SCR
    • Authors: Xiaojiang Yao; Zhu Wang; Shuohan Yu; Fumo Yang; Lin Dong
      Pages: 282 - 288
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Xiaojiang Yao, Zhu Wang, Shuohan Yu, Fumo Yang, Lin Dong
      A series of CeO2 pretreated with different acids (i.e., CH3COOH (HAc), HNO3, HCl, H3PO4, and H2SO4) were prepared with the purpose of exploring the influence of acid pretreatment on the physicochemical property and catalytic performance of CeO2 for NH3-SCR. And then, these catalysts were characterized by means of XRD, Raman, N2-physisorption, H2-TPR, NH3-TPD, in situ DRIFTS, XPS, and NH3-SCR reaction. The obtained results indicate that different acids pretreatment has different influence on the structure, texture, reduction behavior, surface acidity, surface property, and catalytic performance of CeO2. Especially, the sample pretreated by H2SO4 (i.e., CeO2-S catalyst) exhibits the best catalytic performance for NH3-SCR reaction at high temperature among these catalysts due to the largest amount of surface acid sites (especially B acid sites) and Ce3+, as well as the increase of defect sites (such as oxygen vacancy) and the most abundant reducible species. Furthermore, CeO2-S catalyst also exhibits excellent catalytic performance (i.e., above 80% NO conversion) during the whole test of H2O+SO2 resistance, which indicates that it has the potential to be applied in the practical denitration process.
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      PubDate: 2017-06-12T04:50:30Z
      DOI: 10.1016/j.apcata.2017.06.003
      Issue No: Vol. 542 (2017)
       
  • Hydrogenation of γ-valerolactone to 1,4-pentanediol in a continuous
           flow reactor
    • Authors: Daolai Sun; Takeshi Saito; Yasuhiro Yamada; Xin Chen; Satoshi Sato
      Pages: 289 - 295
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Daolai Sun, Takeshi Saito, Yasuhiro Yamada, Xin Chen, Satoshi Sato
      Hydrogenation of γ-valerolactone to 1,4-pentanediol was performed over both precious and base metal catalysts in a continuous flow reactor under H2 pressure. Cu/ZnO catalyst showed the highest catalytic performance for the formation of 1,4-pentanediol from γ-valerolactone. Low reaction temperatures such as 140°C were preferable for achieving 1,4-pentanediol, and high temperatures led to the further conversion of 1,4-pentanediol to 2-methyltetrahydrofuran and 1-pentanol. High H2 pressures and moderate H2 flow rates such as 90cm3 min−1 were effective for the formation of 1,4-pentanediol. Calcination temperature of Cu/ZnO significantly affected its catalytic activity. A Cu/ZnO catalyst with a Cu metal loading of 40wt.% gave the γ-valerolactone conversion of 82.3% with the 1,4-pentanediol selectivity of 99.2% at 140°C under 1.5MPa of H2 pressure, while no decrease in the catalytic activity was observed for 10h.
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      PubDate: 2017-06-12T04:50:30Z
      DOI: 10.1016/j.apcata.2017.05.034
      Issue No: Vol. 542 (2017)
       
  • In-situ XANES and XPD studies of NiO/Ce0.9Zr0.1O2 IT-SOFCs anode
           nanomaterial as catalyst in the CPOM reaction
    • Authors: M.G. Zimicz; F.D. Prado; D.G. Lamas; S.A. Larrondo
      Pages: 296 - 305
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): M.G. Zimicz, F.D. Prado, D.G. Lamas, S.A. Larrondo
      The aim of this paper is to study the oxidation states of metal cations and the changes in the crystalline phases in NiO/Ce0.9Zr0.1O2 nanocatalysts under typical conditions of methane catalytic partial oxidation reaction by in-situ X ray absorption near edge spectroscopy (XANES) and X-ray powder diffraction (XPD) studies. The Ce0.9Zr0.1O2 mixed oxide was obtained by glycine-nitrate-combustion method, being the nickel incorporated by incipient wetness impregnation. The evolution of the crystalline structure with temperature and operating conditions was followed by in-situ XPD experiments and the oxidation states of Ce and Ni cations by in-situ XANES experiments at the Ce-LIII and Ni-K absorption edges. It was observed that NiO is completely reduced to Ni° at temperatures above 650°C while Ce0.9Zr0.1O2 fluorite-like phase showed changes in lattice parameter due to cerium reduction and crystallite growth, but no phase transformations or segregations were observed. It was confirmed that Ni° is the active centre to activate methane molecule while Ce4+/Ce3+ ratio is strongly related with CO/CO2 concentration in the exhaust gas flow.
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      PubDate: 2017-06-12T04:50:30Z
      DOI: 10.1016/j.apcata.2017.05.040
      Issue No: Vol. 542 (2017)
       
  • Comparative roles of Zr4+ and Ni2+ Wells-Dawson hetero-metal substituted
           polyoxometalates on oxidation of chemical contaminants
    • Authors: Spencer L. Giles; Jeffrey G. Lundin; Robert B. Balow; Pehr E. Pehrsson; James H. Wynne
      Pages: 306 - 310
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Spencer L. Giles, Jeffrey G. Lundin, Robert B. Balow, Pehr E. Pehrsson, James H. Wynne
      Rapid oxidation of a persistent organophosphate chemical warfare agent (CWA) analogue by aqueous 15wt% hydrogen peroxide solutions containing hetero-metal substituted Wells-Dawson polyoxometalates (POMs), [Zr(α2-P2W17O61)2]16− and [Ni(α2-P2W17O61)]8−, was accomplished. A novel decontamination method was employed in which oxidation reactions were performed via direct application of aqueous POM solutions onto the CWA analogue, notably without the use of surfactants to promote POM solubility in organic media. POM facilitated reactions occurred at the interface of the aqueous decontamination solution and organic contaminant, the biphasic nature of which affords easy separation and recovery of the POM catalyst for future use. Oxidation of Demeton-S with 15wt% hydrogen peroxide alone was slow with a reaction half-life of 40.9min. Incorporation of Ni2+ and Zr4+ POMs increased the oxidation rate significantly and reduced the reaction half-lives to 20.5 and 2.2min, respectively. The Ni2+ POM increased the rate of reactive species formation by decomposing hydrogen peroxide. The Zr4+ POM when dissolved in 15wt% hydrogen peroxide resulted in a beneficial in situ structural rearrangement, generating the Zr4+ POM species [Zr(H2O)3(α2-P2W17O61)]6− and the Venturello complex ([PO4{W(O)(O2)2}4]3−), with other tungsten peroxo species. The combination of these highly active compounds in solution increased the reaction rate 20-fold over hydrogen peroxide alone, with a half-life of 2.2min.
      Graphical abstract image

      PubDate: 2017-06-16T14:28:50Z
      DOI: 10.1016/j.apcata.2017.06.002
      Issue No: Vol. 542 (2017)
       
  • Consequence of heterogeneity of active sites for reactivity mechanism of
           n-butane isomerization over SO42−/ZrO2-Al2O3 catalyst
    • Authors: Pengzhao Wang; Minxiu Zhang; Wenfang Zhang; Chaohe Yang; Chunyi Li
      Pages: 311 - 316
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Pengzhao Wang, Minxiu Zhang, Wenfang Zhang, Chaohe Yang, Chunyi Li
      The relationship between the heterogeneity of active sites and isomerization mechanism of n-butane over alumina-promoted sulfated zirconia (SZA) was elucidated by two series of catalysts with different surface properties. The incomplete removal of coke deposition leads to a decrease in overall activity without the reduction of the rate of isobutane formation. Subjecting the fresh SZA catalyst to the thermal treatment at 650°C causes a striking decrease in activity, resulting from the decrease in the superacidity and oxidizability of the catalyst. While the thermal treatment at 600°C only selectively suppresses the side reactions. It is found that the peaks in NH3-TPD profiles at 500–700°C are caused by a redox reaction between strongly adsorbed ammonia and superacid sites by in situ NH3-TPD-MS measurements. Thus, this peak reflects the strength of superacidity and oxidizability. At the beginning of the reaction, the effective oxidative and protonative activation routes result in the higher concentration of intermediates, which facilitates the “dimerization-isomerization-cracking” reactions. The incomplete removal of coke and the appropriate decrease in the density of sulfate species on the surface selectively promoted the monomolecular pathway.
      Graphical abstract image

      PubDate: 2017-06-16T14:28:50Z
      DOI: 10.1016/j.apcata.2017.06.005
      Issue No: Vol. 542 (2017)
       
  • Effect of cobalt location in Keggin-type heteropoly catalysts on aerobic
           oxidation of cyclooctane: Experimental and theoretical study
    • Authors: Robert Karcz; Piotr Niemiec; Katarzyna Pamin; Jan Połtowicz; Joanna Kryściak-Czerwenka; Bogna D. Napruszewska; Alicja Michalik-Zym; Małgorzata Witko; Renata Tokarz-Sobieraj; Ewa M. Serwicka
      Pages: 317 - 326
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Robert Karcz, Piotr Niemiec, Katarzyna Pamin, Jan Połtowicz, Joanna Kryściak-Czerwenka, Bogna D. Napruszewska, Alicja Michalik-Zym, Małgorzata Witko, Renata Tokarz-Sobieraj, Ewa M. Serwicka
      A combined experimental and theoretical study of the effect of the polyatom nature (W or Mo) and/or the location of the Co dopant within the heteropoly compound structure on the aerobic liquid phase oxidation of cyclooctane has been carried out. Compounds monosubstituted with Co, either in the cationic position, i.e., CoHPW(Mo)12O40, or within the Keggin anion, i.e., TBA4HPW(Mo)11CoO39 (TBA=tetrabutylammonium) were synthesized and their identity confirmed by characterization with XRF, FTIR, and UV-vis. Oxidation of cyclooctane proceeded via autooxidation mechanism. Experimentally observed patterns of the catalytic behavior depended on the polyatom nature (W or Mo) and/or the location of the Co dopant within the heteropoly compound structure. In general, Mo-based catalysts proved more active than their tungsten counterparts, and location of Co within the Keggin unit more beneficial than addition of cobalt as a counter cation. DFT modeling of Co-substituted Keggin anions and calculations of free enthalpy for the elementary steps of key importance for the chain initiation and the chain propagation/branching provided rationale for the observed effects.
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      PubDate: 2017-06-16T14:28:50Z
      DOI: 10.1016/j.apcata.2017.05.035
      Issue No: Vol. 542 (2017)
       
  • Template-free assembly of nanoporous terpolymer sheets with internal
           heterojunction for photocatalytic hydrogen evolution from water
    • Authors: Shengwu Wen; Ailan Qu; Shikai Wu; Yifan Cui; Xinmei Xu
      Pages: 336 - 342
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Shengwu Wen, Ailan Qu, Shikai Wu, Yifan Cui, Xinmei Xu
      A nanoporous ternary polymer sheets with enhanced photocatalytic activity on H2 evolution from water was prepared by a simple one-pot template-free polymerization in the absence of any catalyst, which was linked by aminal and imine bonds through condensation of melamine (M) and p-phenylenediamine (P) with terephthaldehyde (T). In comparison with binary condensation of M and T, the introduction of P can improve the structural crystallinity, conjugation and regularity of terpolymer by forming imine bonds, thus enhancing visible light absorption and separation of photogenerated electron-holes. Therefore, the terpolymer sheets prepared by simply practical route and cheap raw materials showed high photocatalytic capacity with 74.81μmolh−1 average H2 evolution rate from water under UV–vis light (λ>350nm) without help of any co-catalyst, which is about 4 times of optimized bipolymer (18.56μmolh−1) and about 8 times of graphite-like carbon nitride polymer (pure bulk g-C3N4, 9.43μmolh−1). The internal heterojunction in terpolymer formed by co-existence of aminal and imine blocks perhaps played a similar role as the hybrid of two kinds of semiconductors to promote electron-hole separation. The various linkages between monomers in the polymeric network can provide different functional possibilities, which would expand a new approach to design polymeric photocatalysts.
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      PubDate: 2017-06-16T14:28:50Z
      DOI: 10.1016/j.apcata.2017.06.007
      Issue No: Vol. 542 (2017)
       
  • Design and preparation of hydrated MgAl supported Cu catalysts with high
           alkalinity by MOCVD for the hydrogenolysis of cellulose
    • Authors: Zihui Xiao
      Pages: 343 - 349
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Zihui Xiao
      The unhydrated and hydrated MgAl supported Cu catalysts were successfully prepared by metal-organic chemical vapor deposition (MOCVD) method. The structure properties of metal-organic precursor, supports and catalysts were determined by 1H NMR, FTIR, XRD, N2 physisorption, TEM, N2O titration, and CO2-TPD. The hydration of support had a significant effect on the structure of the final catalysts. The hydrated Mg3Al1 support was benefited to the adsorption and deposition of CuII(hfac)2, resulting in the decrease of the reduction decomposition temperature. Due to the restoration of the layered structure, the 5%Cu/H-Mg3Al1 catalyst had a low BET surface area and pore volume. However, it exhibited higher base sites density and got better performance for cellulose hydrogenolysis compared to the 5%Cu/Mg3Al1 catalyst, which suggested that the hydration before reaction was superior to that during reaction for the catalytic performance, due to the competition between water and products (alcohols with strong adsorption) during reaction, resulting in a decrease in the concentration of in-situ formed surface OH− and the amount of base sites. It was noteworthy that unobvious change in phases of the 5%Cu/H-Mg3Al1 catalyst was observed before and after reaction, which provided a promising way to establish the relationship between structure and catalytic performance.
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      PubDate: 2017-06-16T14:28:50Z
      DOI: 10.1016/j.apcata.2017.06.012
      Issue No: Vol. 542 (2017)
       
  • Solvent-free “green” amidation of stearic acid for synthesis of
           biologically active alkylamides over iron supported heterogeneous
           catalysts
    • Authors: Päivi Mäki-Arvela; Jeanne Zhu; Narendra Kumar; Kari Eränen; Atte Aho; Johan Linden; Jarno Salonen; Markus Peurla; Anton Mazur; Vladimir Matveev; Dmitry Yu. Murzin
      Pages: 350 - 358
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Päivi Mäki-Arvela, Jeanne Zhu, Narendra Kumar, Kari Eränen, Atte Aho, Johan Linden, Jarno Salonen, Markus Peurla, Anton Mazur, Vladimir Matveev, Dmitry Yu. Murzin
      Stearoyl ethanolamine was synthesized by amidation of stearic acid with ethanolamine in solventless conditions. Iron containing heterogeneous catalysts supported on SiO2, Al2O3, Beta (BEA), ZSM-12 (MTW) and Ferrierite (FER) were used in this work. Sn-modified Ferrierite and H-Ferrierite were also studied for comparison. Fe-modified catalysts synthesized using solid state ion-exchange and evaporation impregnation methods, were thoroughly characterized with X-ray powder diffraction, scanning electron microscope, FTIR with pyridine, nitrogen adsorption, energy dispersive X-ray microanalysis and Mössbauer spectroscopy. The highest conversion was obtained with Fe-H-FER-20 at 140°C in 1h giving 61% conversion and 98% selectivity towards the desired amide. The catalytic performance in terms of turnover frequency per mole of iron was achieved with the catalyst exhibiting the largest amount of Fe3+ species, optimum acidity and a relatively low Brønsted to Lewis acid site ratio.
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      PubDate: 2017-06-16T14:28:50Z
      DOI: 10.1016/j.apcata.2017.06.006
      Issue No: Vol. 542 (2017)
       
  • Desulfurization process conciliating heterogeneous oxidation and liquid
           extraction: Organic solvent or centrifugation/water'
    • Authors: Susana O. Ribeiro; Lucie S. Nogueira; Sandra Gago; Pedro L. Almeida; Marta C. Corvo; Baltazar de Castro; Carlos M. Granadeiro; Salete S. Balula
      Pages: 359 - 367
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Susana O. Ribeiro, Lucie S. Nogueira, Sandra Gago, Pedro L. Almeida, Marta C. Corvo, Baltazar de Castro, Carlos M. Granadeiro, Salete S. Balula
      The present work presents a strategic oxidative desulfurization system able to efficiently operate under sustainable conditions, i.e. using an eco-friendly oxidant and without the need of extractive organic solvents. The catalytic performance of Eu(PW11O39)2@aptesSBA-15 was evaluated for the oxidative desulfurization of a multicomponent model diesel using a solvent-free or biphasic systems. The results reveal its remarkable desulfurization performance achieving complete desulfurization after just 2h of reaction. Moreover, the composite has shown a high recycling ability without loss of catalytic activity for ten consecutive ODS cycles. Interestingly, under solvent-free conditions it was possible to maintain the desulfurization efficiency of the biphasic system while being able to avoid the use of harmful organic solvents. In this case, a successful extraction of oxidized sulfur compounds was found conciliating centrifugation and water as extraction solvent. Therefore, this work reports an important step towards the development of novel eco-sustainable desulfurization systems with high industrial interest.
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      PubDate: 2017-06-16T14:28:50Z
      DOI: 10.1016/j.apcata.2017.05.032
      Issue No: Vol. 542 (2017)
       
  • Development of novel efficient 2D nanocomposite catalyst towards the
           three-component coupling reaction for the synthesis of
           imidazo[1,2-a]pyridines
    • Authors: Najrul Hussain; Pranjal Gogoi; Manash R. Das; Pinaki Sengupta; Vladimir E. Fedorov; Igor P. Asanov; Mariia N. Kozlova; Sofya B. Artemkina
      Pages: 368 - 379
      Abstract: Publication date: 25 July 2017
      Source:Applied Catalysis A: General, Volume 542
      Author(s): Najrul Hussain, Pranjal Gogoi, Manash R. Das, Pinaki Sengupta, Vladimir E. Fedorov, Igor P. Asanov, Mariia N. Kozlova, Sofya B. Artemkina
      Two dimensional (2D) materials such as graphene and functionalized hexagonal boron nitride (h-BN) supported copper catalysts (CuO/rGO, CuO/h-BN, Cu(0)/rGO, Cu(0)/h-BN, CuS/rGO and CuS/h-BN) were prepared, characterized and evaluated their catalytic activity for the synthesis of imidazo[1,2-a]pyridines via one pot three component reaction between 2-aminopyridine, aldehyde and terminal alkynes. The imidazo[1,2-a]pyridines are an imperative class of nitrogen ring containing heterocyclic compounds which has wide range of applications in medicinal chemistry and drug molecule production. The reported synthetic protocol provides a rapid access to substituted imidazo[1,2-a]pyridines with excellent yields. CuO/rGO nanocomposite material was found to be highly active catalyst for the aforementioned reaction. The advantages of our protocol for the preparation of imidazo[1,2-a]pyridines over other previously reported includes shorter reaction times, functional group tolerance, recyclable catalyst and additive-free.
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      PubDate: 2017-06-16T14:28:50Z
      DOI: 10.1016/j.apcata.2017.05.033
      Issue No: Vol. 542 (2017)
       
  • Deactivation study of carbon-supported ruthenium catalyst with potassium
           promoter
    • Authors: Bingyu Lin; Yunjie Guo; Jingdong Lin; Jun Ni; Jianxin Lin; Lilong Jiang; Yong Wang
      Pages: 1 - 7
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): Bingyu Lin, Yunjie Guo, Jingdong Lin, Jun Ni, Jianxin Lin, Lilong Jiang, Yong Wang
      Carbon-supported Ru catalyst with alkali promoter is arguably the most significant advancement in ammonia synthesis. However, the insufficient stability of this type of catalysts greatly limits their applications, and carbon methanation is often considered as the reason for deactivation. Here we report that there is no clear correlation between carbon methanation and the loss of activity. Rather, carbon oxidation at high temperature, especially via the formation of carbon monoxide, was found to have a strong influence on the activity and stability of Ru catalysts. As a result, there is a significant increase in carbon loss, leading to the sintering of Ru particles and thereby altered hydrogen adsorption. Consequently, catalytic activity and stability of Ru/C catalysts are reduced. This finding contributes to the development of strategies to design carbon-supported metal catalysts with high activity and stability.
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      PubDate: 2017-05-08T07:54:19Z
      DOI: 10.1016/j.apcata.2017.04.020
      Issue No: Vol. 541 (2017)
       
  • A DFT study of ethane activation on IrO2(110) surface by
           precursor-mediated mechanism
    • Authors: Thong Le Minh Pham; Santhanamoorthi Nachimuthu; Jer-Lai Kuo; Jyh-Chiang Jiang
      Pages: 8 - 14
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): Thong Le Minh Pham, Santhanamoorthi Nachimuthu, Jer-Lai Kuo, Jyh-Chiang Jiang
      The adsorption configurations of ethane on IrO2(110) surface have been investigated using density functional theory (DFT) methods. We find that ethane is most stably adsorbed on IrO2(110) surface by interacting with two adjacent Ircus atoms, which is mainly driven by agostic interaction. We have also performed an elementary step analysis for the ethane dehydrogenation via precursor mediated mechanism on IrO2(110) surface. Our results indicate that the activation of ethane on IrO2(110) surface is both thermodynamically and kinetically favorable reaction, which is expected to occur at low temperature. Further, we have investigated the role of van der Walls corrections on adsorption and the reaction energetics of ethane dehydrogenation. The results indicate that the contribution of van der Walls corrections has a major impact on ethane adsorption and it facilitates the ethane activation via precursor mediated mechanism instead of desorption.
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      PubDate: 2017-05-08T07:54:19Z
      DOI: 10.1016/j.apcata.2017.04.018
      Issue No: Vol. 541 (2017)
       
  • Catalytic oxidative dehydrogenation of carveol to carvone over the
           phthalocyanine complex FePcCl16 immobilized on the mesoporous silica
           SBA-15
    • Authors: Diana-Lucía Grajales; Lina-María González; Aída-Luz Villa
      Pages: 15 - 24
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): Diana-Lucía Grajales, Lina-María González, Aída-Luz Villa
      The immobilization of the FePcCl16 complex on the mesoporous silica SBA-15 and its performance in the eco-friendly oxidative dehydrogenation of carveol to carvone in the presence of t-butyl hydroperoxide (TBHP) under mild conditions is reported. The successful covalently anchored of FePcCl16 complex inside the pores of SBA-15, without complex or support damage, was confirmed by XRD, BET, UV–vis, SEM, TEM and Raman analysis. The best results achieved were after 1h of reaction, with 40% carvone selectivity and a carveol conversion around of 75%; carvone selectivity decayed when carveol conversion increased. Several mechanisms and rate equations derived from the kinetic models based on the Power Law, Langmuir-Hinshelwood, and Eley-Rideal model were proposed. Although the Power Law model showed the best mathematical fitting, the Eley-Rideal model seems to explain better the chemical sense of reaction. FePcCl16-NH2-SBA-15 catalyst was stable under the reaction conditions and it can be used up to twice without significant decrease in its catalytic activity.
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      PubDate: 2017-05-08T07:54:19Z
      DOI: 10.1016/j.apcata.2017.04.019
      Issue No: Vol. 541 (2017)
       
  • Biphasic TiO2 microspheres/reduced graphene oxide for effective
           simultaneous photocatalytic reduction and oxidation processes
    • Authors: Hanan H. Mohamed
      Pages: 25 - 34
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): Hanan H. Mohamed
      Simultaneous photoassisted oxidation of organic dyes (methylene blue (MB), crystal violet (CV)) and reduction of metal ions (Ag(I), Cu(II)) were studied using new synthesized hierarchical structures of anatase/rutile TiO2 microspheres-reduced graphene oxide (TiO2-rGO) nanocomposites. Interestingly, rutile/anatase phase transformation was observed upon changing the graphene oxide content. An increasing of the anatase/rutile ratio upon increasing the graphene oxide content was observed. Additionally, the synthesized nanocomposites show enhanced photocatalytic activity either for the reduction of heavy metal ions or for the degradation of the dyes compared to pristine TiO2 nanoparticles. A highest activity has been achieved using the nanocomposite containing 62% anatase and 38% rutile. This enhancement in the photocatalytic activity can be attributed to the synergetic effect between anatase and rutile in the synthesized TiO2 microspheres composites. Furthermore, The study of the effect of various concentrations of metal ions shows that increasing the metal ions concentration highly promoted the photocatalytic degradation of the organic dyes. A complete decoloration of both dyes has been observed within very short time. Furthermore, enhancement of the photocatalytic reduction of the metal ions was achieved by increasing the dye concentration. Therefore, an obvious synergistic effect was observed leading to the enhancement of both the photocatalytic and reduction. The results show a cost effective method for a simultaneous removal of organic and inorganic pollutants from wastewater.
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      PubDate: 2017-05-12T16:26:40Z
      DOI: 10.1016/j.apcata.2017.04.017
      Issue No: Vol. 541 (2017)
       
  • Use of tetraethylammonium bicarbonate as a precipitation agent on the
           preparation of coprecipitated Cu/ZnO catalysts
    • Authors: Cheonwoo Jeong; Taewoo Kim; Jinsung Kim; Young-Woong Suh
      Pages: 35 - 41
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): Cheonwoo Jeong, Taewoo Kim, Jinsung Kim, Young-Woong Suh
      Cu/ZnO catalysts were prepared by coprecipitation using tetraethylammonium bicarbonate (TEA+HCO3 −), and their properties and methanol synthesis activities were compared to those of the catalysts prepared using Na+HCO3 − usually employed for commercial Cu/ZnO/(Al2O3) catalysts. When washed fully, TEA+- and Na+-based precursors showed typical zincian malachite (zM) without any other structures, and both catalysts obtained after calcination and H2 reduction exhibited the similar specific copper surface area and, in turn, the similar methanol productivity. Since this result explains that TEA+ does not affect zM structure if Cu,Zn precipitate is fully washed, no washed and less washed TEA+- and Na+-based precursors were prepared. It was interesting that all TEA+-based catalysts exhibited the similar methanol productivity irrespective of the washing efficiency whereas Na+-based catalyst containing more residual Na+ showed the smaller copper surface area and lower methanol productivity (i.e., linear correlation between the two parameters). This resulted from the inhibiting effect of Na+ on the degree of Cu2+ substitution by Zn2+ and the formation of high-temperature carbonate, consequently leading to a lower catalytic activity. These negative effects of Na+ were absent or lessened when TEA+HCO3 − was used as a precipitation agent, which is effective in preparing an active methanol synthesis catalyst.
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      PubDate: 2017-05-12T16:26:40Z
      DOI: 10.1016/j.apcata.2017.04.023
      Issue No: Vol. 541 (2017)
       
  • Simultaneous removal of soot and NOx with Ru-Ir/TiO2 catalyst under
           oxygen-rich condition
    • Authors: Rongshu Zhu; Qingyun Yan; Jiansheng He; Gang Cao; Feng Ouyang
      Pages: 42 - 49
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): Rongshu Zhu, Qingyun Yan, Jiansheng He, Gang Cao, Feng Ouyang
      A series of Ru-Ir bimetallic catalysts with different mass ratios (Ru-Ir/TiO2, Ru:Ir=9:1, 7:3, 5:5, 3:7, 1:9) were prepared by iso-volumetric impregnation method. The activities of the catalysts for simultaneous removal of soot and NOx were investigated by Temperature Programmed Surface Reaction (TPSR) technique, and the properties of the catalysts were characterized by various analysis techniques, such as XPS, XRD, TEM, H2-TPR, H2-TPD and nitrogen adsorption. The results indicated that Ru-Ir/TiO2 bimetallic catalysts had better activity for simultaneous removal of soot and NOx than Ru/TiO2 or Ir/TiO2. When the mass ratio of Ru:Ir was 9:1, the catalyst showed the best catalytic activity. The peak temperature of soot oxidation was 437°C and the highest conversion efficiency of NOx was 42.6%. On the basis of the characterization of the catalysts, the relationship between the catalytic activity of Ru-Ir/TiO2 and the synergetic roles of Ru and Ir was discussed.
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      PubDate: 2017-05-12T16:26:40Z
      DOI: 10.1016/j.apcata.2017.04.014
      Issue No: Vol. 541 (2017)
       
  • Fischer-Tropsch synthesis to light olefins over iron-based catalysts
           supported on KMnO4 modified activated carbon by a facile method
    • Authors: Zhipeng Tian; Chenguang Wang; Zhan Si; Longlong Ma; Lungang Chen; Qiying Liu; Qi Zhang; Hongyu Huang
      Pages: 50 - 59
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): Zhipeng Tian, Chenguang Wang, Zhan Si, Longlong Ma, Lungang Chen, Qiying Liu, Qi Zhang, Hongyu Huang
      Fischer-Tropsch synthesis to light olefins (FTO) using biomass-derived syngas is an economical and renewable way to produce olefins. By using KMnO4 as precursor, a number of low cost iron based catalysts was produced and their FTO performances were tested. Firstly, a series of KMnO4 solutions with different concentrations were used to pretreat activated carbon (AC). Support was coated uniformly by K-doped birnessite MnO2 and substantial amount of surface oxygen-containing groups and defects were obtained simultaneously. Then, iron catalysts loaded on KMnO4 modified AC support was prepared by incipient wetness impregnation method. Characterization of the catalyst showed that α-Fe2O3 nanoparticles were uniformly loaded on the surface of KMnO4 treated AC. The valent of manganese (IV) was then transformed into Mn (II) and Mn (III) with AC served as a reducing agent. The redox reaction during preparation leads to a lower Mn chemical valence, which makes it easier to further reduction. More defects on support after calcination procedure were also observed due to the enrichment of oxygen-containing groups, which was helpful in anchoring α-Fe2O3 particles and decreasing its average particle size. High-content manganese played not only as a structural promoter to anchor Fe2O3 nanoparticles, but also a H2 adsorption competitor that decreased H2/CO ratio over active sites to reduce the possibility of further hydrogenation of olefins. The KMnO4 modified iron catalysts exhibited high CO conversion and olefins selectivity (∼40%) due to the improved distribution of iron and the auxiliary functions of Mn. Residual potassium is also in favor of the formation of iron carbides to increase CO conversion.
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      PubDate: 2017-05-12T16:26:40Z
      DOI: 10.1016/j.apcata.2017.05.001
      Issue No: Vol. 541 (2017)
       
  • Selective hydrogenolysis of αO4, βO4, 4O5 CO bonds of lignin-model
           compounds and lignin-containing stillage derived from cellulosic
           bioethanol processing
    • Authors: B. Gómez-Monedero; M.P. Ruiz; F. Bimbela; J. Faria
      Pages: 60 - 76
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): B. Gómez-Monedero, M.P. Ruiz, F. Bimbela, J. Faria
      Benzyl phenyl ether (BPE), phenethyl phenyl ether (PPE) and diphenyl ether (DPE) have been selected as model compounds of the most abundant and significant ether linkages found within the complex structure of lignin (e.g. αO4, βO4, and 4O5, respectively). The catalytic hydrogenolysis of these compounds has been carried out using several Ru, Pd and Ni catalysts supported over different metal oxides (e.g. Al2O3, ZrO2, TiO2) and carbon materials (e.g. active carbon, multiwall carbon nanotubes). The conversion of these compounds at relevant hydroprocessing conditions (150°C, 25bar-g in H2 atmosphere) is much dependent on the labile nature of the relevant ether bonds of the selected model compounds. Conversion levels for the three compounds increases in the following order: DPE (4O5 linkage)<PPE (βO4)<BPE (αO4). Product distribution is also dependent on the chemical structure of the raw material subjected to catalytic hydroprocessing, with BPE and DPE mainly yielding aromatic monomers, whilst fully saturated monomers are the main reaction products when PPE is hydroprocessed. The reaction mechanisms upon hydroprocessing vary from one model compound to another, being hydrogenolysis the prevailing route in the catalytic hydroprocessing of BPE and DPE, whereas competing reaction pathways between dimer hydrogenation and hydrogenolysis of the CO bond occur for the PPE molecule. The conversion and selectivity to relevant hydrogenolysis products are also dependent on the catalyst used. Ru-based catalysts are the most active followed by Pd −based and Ni-based, whereas selectivity to aromatic monomers increases in the reverse order (Ni>Pd>Ru). The catalytic systems with easier reducible species performes better in the conversion of the dimer models. Besides, a preliminary study on the catalytic depolymerization of a real lignin stream (lignin-containing 2G bioethanol plants stillage) has been carried out. Detailed characterization by 13C-1H heteronuclear single-quantum correlation spectroscopy (HSQC) showed that on 5wt.% Ru/C it is possible to achieve 50% desapearance of the most abundant lignin ether bond (i.e. βO4) and liquid yields above 50wt.%.
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      PubDate: 2017-05-17T18:16:52Z
      DOI: 10.1016/j.apcata.2017.04.022
      Issue No: Vol. 541 (2017)
       
  • Effect of Cr2O3 loading on the properties and cracking activity of
           Pt/Cr2O3-ZrO2
    • Authors: N.H.R. Annuar; S. Triwahyono; A.A. Jalil; N. Basar; T.A.T. Abdullah; A. Ahmad
      Pages: 77 - 86
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): N.H.R. Annuar, S. Triwahyono, A.A. Jalil, N. Basar, T.A.T. Abdullah, A. Ahmad
      The effects of Cr2O3 loading ranging from 1 to 12wt.% on the properties, structure and isopropylbenzene (IPB), 1,4-diisopropylbenzene (DIPB) and 1,3,5-triisopropylbenzene (TIPB) hydrocracking activities of Pt/Cr2O3-ZrO2 (Pt/CrZr) were studied. The properties of Pt/CrZr were characterized with XRD, BET, IR and UV–vis spectrometer. The acidity was determined by 2,6-lutidine adsorbed IR spectroscopy. The introduction of Cr2O3 on ZrO2 intensified continuously the tetragonal phase of ZrO2 and bulk crystalline Cr2O3, while the surface area and acidity passed through a maximum of Cr2O3 loading at 8wt.%. The IR study confirmed the presence of CrO stretching bands at 1035 and 1013cm−1 on Pt/CrZr. No dioxo species involving the stretching modes of OCrO existed. H2 and 2,6-lutidine showed different interactions with Pt/CrZr in which the band at 1013cm−1 is more extensively affected with 2,6-lutidine adsorption for all Pt/CrZr and the band at 1035cm−1 is more affected with H2 adsorption for Cr2O3 loading at≤8wt.%. While, at >8wt.% Cr2O3 loading, the H2 is more interacted with the band at 1013cm−1. These results suggested that the absorbance bands at 1013 and 1035cm−1 are assignable to the stretching of the CrO which is connected to the other Cr through O and CrO which is connected to cus Zr4+ through O, respectively. The catalyst with 8wt.% loading performed with a maximum activity in IPB, DIPB and TIPB hydrocracking at 523K which may be due to presence of CrO band at 1035cm−1 which extensively interacted with H2 to form protonic acid sites via a hydrogen spillover phenomenon. In fact, Cr2O3 loading at 8wt.% possessed strong permanent Lewis acid sites which play an important role in the stabilization of an electron during the formation of protonic acid sites.
      Graphical abstract image

      PubDate: 2017-05-17T18:16:52Z
      DOI: 10.1016/j.apcata.2017.05.006
      Issue No: Vol. 541 (2017)
       
  • A review on reaction mechanisms of metal-catalyzed deoxygenation process
           in bio-oil model compounds
    • Authors: Andrew Ng Kay Lup; Faisal Abnisa; Wan Mohd Ashri Wan Daud; Mohamed Kheireddine Aroua
      Pages: 87 - 106
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): Andrew Ng Kay Lup, Faisal Abnisa, Wan Mohd Ashri Wan Daud, Mohamed Kheireddine Aroua
      Bio-oil is a potential liquid fuel source which can be produced through the pyrolysis of biomass. Catalytic deoxygenation is an instrumental step for the defunctionalization of bio-oil which will result in liquid fuel which is of lower oxygen content and higher heating value. Numerous studies were done to investigate the deoxygenation mechanisms and the kinetics of various bio-oil model compounds. In this review, heterogeneous metal-catalyzed deoxygenation mechanisms of oxygenated model compounds with functional groups such as phenolics, furans, ethers, carboxylic acids, aldehydes, ketones and alcohols were compared and discussed. The limitations, benefits and feasibilities of such mechanisms were also presented in this article. The discussions on the classes of model compounds and the bonding configurations of oxygenated compounds have also shown that there is a strong correlation between these parameters and the reaction pathways. Hence, this review presented a summary of the model compound based approach researches which would be useful in correlating such knowledge with the actual bio-oil deoxygenation process. Several outlooks on the deoxygenation reactivity of model compounds were also presented in this article based on the studies on the literatures.
      Graphical abstract image

      PubDate: 2017-05-17T18:16:52Z
      DOI: 10.1016/j.apcata.2017.05.002
      Issue No: Vol. 541 (2017)
       
  • A scalable production of anisonitrile through organoselenium-catalyzed
           dehydration of anisaldoxime under solventless conditions
    • Authors: Xiaobi Jing; Tingting Wang; Yuanhua Ding; Lei Yu
      Pages: 107 - 111
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): Xiaobi Jing, Tingting Wang, Yuanhua Ding, Lei Yu
      An organoselenium-catalyzed dehydration reaction of anisaldoxime to produce the useful fine chemical anisonitrile was achieved under solventless conditions without using any dehydrant. Simple PhSe(O)OH could be employed as the recyclable and reusable catalyst without obvious deactivation, and the reaction generated no wastes at all. By an easily operable distillation process, the product could be isolated in high purity, as confirmed by NMR spectroscopic analysis. The reaction was scalable to at least kilogram-scale with excellent carbon mass balance at 99.3%, showing very great potential of the method in industrial-scale production. The mechanism of the reaction was also discussed based on the experimental findings.
      Graphical abstract image

      PubDate: 2017-05-17T18:16:52Z
      DOI: 10.1016/j.apcata.2017.05.007
      Issue No: Vol. 541 (2017)
       
  • Organic ligands incorporated hypercrosslinked microporous organic nanotube
           frameworks for accelerating mass transfer in efficient heterogeneous
           catalysis
    • Authors: Yang Xu; Tianqi Wang; Zidong He; Minghong Zhou; Wei Yu; Buying Shi; Kun Huang
      Pages: 112 - 119
      Abstract: Publication date: 5 July 2017
      Source:Applied Catalysis A: General, Volume 541
      Author(s): Yang Xu, Tianqi Wang, Zidong He, Minghong Zhou, Wei Yu, Buying Shi, Kun Huang
      Microporous organic polymers (MOP) usually have dominated micropores smaller than 2nm, which may restrict their performance in the mass transfer processes. Adding mesopores into microporous materials to form hierarchical structure has been recognized as a promising route to eliminate their transport limitations and further improve their value in applications. Here we report a straightforward method for the synthesis of organic ligands incorporated hypercrosslinked microporous organic nanotube frameworks (O-HMONFs) via Friedel-Crafts hyper-crosslinking reaction of small aromatic organic ligands with core-shell bottlebrush copolymers as platforms for heterogeneous catalysts. In particular, because of the mesopores produced by the core degradation, O-HMONFs-based catalysts showed more comparable activities than the corresponding disordered MOP-based catalyst and homogeneous molecular catalyst under similar conditions. More importantly, this method might be suitable for various aromatic organic ligands and could be used as a general approach to produce a variety of functional microporous organic nanotube frameworks.
      Graphical abstract image

      PubDate: 2017-05-17T18:16:52Z
      DOI: 10.1016/j.apcata.2017.05.005
      Issue No: Vol. 541 (2017)
       
  • A safer and greener chlorohydrination of allyl chloride with H2O2 and HCl
           over hollow titanium silicate zeolite
    • Authors: Xinxin Peng; Changjiu Xia Min Lin Xingtian Shu Bin Zhu
      Abstract: Publication date: 5 August 2017
      Source:Applied Catalysis A: General, Volume 543
      Author(s): Xinxin Peng, Changjiu Xia, Min Lin, Xingtian Shu, Bin Zhu, Baorong Wang, Yao Zhang, Yibin Luo, Xuhong Mu
      Industrial production of dichloropropanols through chlorohydrination of allyl chloride suffers from a series of disadvantages such as use of hazardous Cl2, low atom economy, low dichloropropanol concentration and serious pollution. In this work, a safer and greener route for chlorohydrination of allyl chloride with H2O2 and HCl over hollow titanium silicate (HTS) at mild condition is developed. Unlike the traditional Cl2-based chlorohydrination, this novel method is initiated via synergistic effect of Lewis acidity (HTS) and Brønsted acidity (HCl) to promote occurrence of oxidation, protonation and nucleophilic reaction of allyl chloride simultaneously and hence dichloropropanols are generated. Owing to a completely different reaction route, the formation of 1,2,3-trichloropropane by-product is depressed and the content of dichloropropanol exceeded 22wt%, which increase by about 4 times compared with traditional Cl2-based chlorohydrination (the content of dichloropropanol is below 4wt%). At the optimized conditions, both of the allyl chloride conversion and dichloropropanol selectivity could approach 99% simultaneously and the waste is minimized. What’s more, the HTS was reusable. Concentrated HCl solution treatment was adopted to test HTS’s stability. The characterization and catalytic evaluation results reveal that, although parts of the framework Ti species have transformed into non-framework Ti and then leached into the solution, HTS remains structural stable, and the allyl chloride conversion and dichloropropanol selectivity didn’t decrease obviously during the treatment.
      Graphical abstract image

      PubDate: 2017-06-21T17:06:01Z
       
  • Hydrogenation of CO2 over supported noble metal catalysts
    • Authors: Paraskevi Panagiotopoulou
      Abstract: Publication date: Available online 26 May 2017
      Source:Applied Catalysis A: General
      Author(s): Paraskevi Panagiotopoulou
      The catalytic activity of supported noble metal catalysts for the CO2 methanation reaction has been investigated with respect to the nature (Rh, Ru, Pt, Pd), loading (0.1-5.0wt.%) and mean crystallite size (1.3-13.6nm) of the dispersed metallic phase. It has been found that the turnover frequency (TOF) of CO2 conversion for TiO2-supported catalysts increases following the order of Pd < Pt < Ru < Rh, with Rh being about 3 times more active than Pd. Selectivity toward methane depends strongly on the noble metal catalyst employed and is significantly higher for Rh and Ru catalysts compared to Pt and Pd, which mainly promote production of CO via the RWGS reaction. Conversion of CO2 at a given temperature increases significantly with increasing Ru loading in the range of 0.1-5.0wt.%. Results of kinetic measurements show that the CO2 hydrogenation reaction is structure sensitive, i.e., catalytic activity is strongly influenced by metal crystallite size. In particular, for Ru/TiO2 and Ru/Al2O3 catalysts, the normalized turnover frequency (TOF divided by the length of the perimeter of the metal-support interface) increases by two orders of magnitude with increasing ruthenium crystallite size in the range of 0.9-4.2nm and 1.3-13.6nm, respectively. FTIR experiments provide evidences that CO2 hydrogenation reaction occurs via intermediate formation of adsorbed CO species (Rux-CO, Run+(CO)x, (TiO2)Ru-CO) produced via the RWGS reaction. Part of this species interacts with adsorbed hydrogen atoms producing methane, whereas the remaining species desorbs to yield CO in the gas phase. The CO2 hydrogenation pathway does not change with variation of Ru crystallite size. However, the relative intensity of the band due to CO species linearly bonded on reduced Ru crystallites (Rux-CO) increases significantly with increasing Ru particle size, indicating that Rux-CO species could potentially being the reactive surface intermediates.
      Graphical abstract image

      PubDate: 2017-05-28T08:51:52Z
       
 
 
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