Authors:SAIFULLAHI LAWAL MUHAMMAD, Muhammad Bashir Ibrahim Pages: 8 - 4(2022) 25 Abstract: The inhibition action and adsorption behavior of Azadirachta indica bark extract was studied on zinc in 0.25 M HNO3 solution using weight loss, FT-IR and SEM analysis. The result of the findings show that inhibition efficiency of the extract increases with increase in inhibitor concentration and decrease with rise in temperature. Corrosion rate was found to increase with rise in temperature and decrease with increase in inhibitor concentration. FT-IR and SEM analysis shows that there is adsorption of inhibitor molecules on metal surface which lead to decrease in corrosion rate. Adsorption isotherm study shows that experimental data obey Freundlich isotherm and the mechanism of adsorption follow physisorption. Adsorption thermodynamic study indicates feasible and spontaneous process from the large negative value of free energy. The value of enthalpy are all positives indicating endothermic nature of adsorption. The result of activation energy was found to be higher in the presence of inhibitor than its absence indicating the decrease in energy barrier of zinc dissolution process. PubDate: 2022-12-30 DOI: 10.48422/IMIST.PRSM/ajees-v8i4.34608 Issue No:Vol. 8, No. 4 (2022)
Authors:Abdurrahman hudu, A.S. Muhammad Pages: 8 - 4(2022) 27 Abstract: ABSTRACTIn the present work, the impact of Mn-doped ZnO on photocatalytic activity of ZnO nanoparticles and potential antimicrobial properties was studied. ZnO and Mn-doped ZnO were successfully synthesized by precipitation and co-precipitation method, respectively. The catalysts were characterized by scanning electron microscopy (SEM), x-ray diffraction (XRD) energy dispersive X-ray (EDX) spectroscopy and pH at point of zero charge. The structural and optical properties of the nanoparticles elucidated that the Mn2+ ions have substituted the Zn2+ ions without changing the wurtzite structure of ZnO. The band gap energy of ZnO and Mn-doped ZnO were found to be 3.15 and 2.77 eV respectively. The pH at point of zero charge for undoped and doped ZnO were found to be 9.1 and 7.5 respectively. The photocatalytic activity of synthesized ZnO and Mn doped ZnO NPs on degradation of RB dyes were examined. Photocatalytic studies revealed that the maximum percentage degradation RB is 73%.This indicates that the doping of Mn generally leads to enhanced photocatalytic activity of ZnO. Photodegradation of RB were fitted into pseudo zero order, pseudo first order and pseudo second order models and pseudo-first-order kinetics best fitted. PubDate: 2022-12-30 DOI: 10.48422/IMIST.PRSM/ajees-v8i4.34946 Issue No:Vol. 8, No. 4 (2022)
Authors:Musa Rabiu Abdullahi, F.O. Nwosu Pages: 8 - 4(2022) 28 Abstract: Copper ferrite activated carbon nanocomposites (CFACNC) has been used as adsorbent for the removal of mordant black 11 dye from aqueous solution and real tannery effluents. The nanocomposites was characterized using Fourier Transform infrared (FTIR), Brunauer–Emmet–Teller (BET), Scanning electron microscope (SEM) and Transmission electron microscope (TEM). Batch adsorption experiments were investigated and the effects of various parameters were studied and their optimum conditions were then applied on the selected real tannery effluents. The study showed that the maximum adsorption capacities for dye onto CFACNC at pH 4 were found to be 0.73 and 4.13 mg/g for tannery A and B respectively. Langmuir isotherm described the adsorption of dye onto CFACNC while kinetic studies followed pseudo second-order.Keywords: Adsorption, tannery, effluents , dye PubDate: 2022-12-30 DOI: 10.48422/IMIST.PRSM/ajees-v8i4.35249 Issue No:Vol. 8, No. 4 (2022)
Authors:Volodymyr Valentynovych Tkach, Marta V. Kushnir; Nataliia M. Storoshchu Bogdan D. Storoshchuk, Sílvio C. de Oliv Yana G. Ivanushko, Yevgeniya V. Nazymok, , Adriano O. da Silva, Olga V. Luganska, Yulia V. Yeshchenko, Lyudmyla O. Omelianchyk, , Viktoria O. Gencheva, Vira V. Kopiika, Petro I. Yagodynets´, Zholt O. Kormosh, Yulia V. Palytsia Pages: 8 - 4(2022) 30 Abstract: The possibility of paraquat electrochemical detection, realized by conducting polymer electrode, doped by vanadium dioxide, was analyzed by theoretical point of view. It was shown, that the conducting polymer composite with VO2 may serve as an excellent electrode modifier for paraquat electrochemical detection. The steady-state may be maintained stable in the vast parameter region. The possibility for electrochemical instabilities in this system has also been studied. PubDate: 2022-12-30 DOI: 10.48422/IMIST.PRSM/ajees-v8i4.33280 Issue No:Vol. 8, No. 4 (2022)
Authors:Alaba Joseph Adebayo, Joseph Kolawole Ogunjobi, Olugbenga O Oluwasina, Labunmi Lajide Pages: 8 - 4(2022) 30 Abstract: Environmental concerns have triggered the search for green chemicals for the replacement of fossil-based chemicals. The need for a cleaner environment is the pivot for the search for green chemicals from biomass as a replacement for the fossil-based chemicals. Thus, the present study focuses on the isolation, optimization, liquefaction, and characterization of lignin from agricultural wastes namely: ground nutshell (GNS), palm front base (PFB), palm kernel shell (PKS), male palm fruit (MPF) and baobab pod shell (BPS). Lignin yield was optimized by varying concentrations of sodium hydroxide, biomass to liquor ratio, time, and temperature. From the results, PKS had the highest lignin yield (100 %) while GNS gave the lowest yield (13.7%). The best optimization condition was 25% w/v NaOH concentration, 130 oC, and biomass to liquor ratio 1:40 for PKS for a period of 120 min. The lignin obtained from PKS was liquefied, using polyethylene glycol 400 (PEG400) and ethylene glycol (EG) as liquefying solvents. However, the lignin for gas chromatography-mass spectrometer (GC-MS) analysis was isolated using the copper alkaline extraction method. Lignin samples were characterized using Fourier Transform Infrared (FTIR) spectroscopy and gas chromatography-mass spectrometer (GC-MS). The results obtained from the characterization showed monomeric phenolic products with fewer ether bonds present. Similarly, the extent of liquefaction and the quality of liquefied products (bio-polyol) from the respective solvents used were observed. The two bio-polyols (PEG400 and EG) had hydroxyl numbers: 450 mg KOH/g and 445 mg KOH/g, liquefaction yield: 93.22% and 92.22%, and residue contents: 3.39% and 3.49% respectively. The qualities of the obtained bio-polyol are suitable for rigid bio-based foam synthesis. PubDate: 2022-12-30 DOI: 10.48422/IMIST.PRSM/ajees-v8i4.34570 Issue No:Vol. 8, No. 4 (2022)