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Journal of Sustainable Metallurgy
Number of Followers: 4  Hybrid journal (It can contain Open Access articles)ISSN (Print) 2199-3823 - ISSN (Online) 2199-3831 Published by Springer-Verlag  [2469 journals]
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- A Combined Approach for Green Supply Chain Management Performance
Measurement in a Steel Manufacturing Company: An Indonesian Case-
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Abstract: The purpose of this research is to provide a complete method for measuring the performance of green supply chain management (GSCM) in the steel manufacturing sector using a combined approach. This study is conducted on an integrated system based on four things: the design of the GSCM performance measurement model based on the Seven Sink Performance Model, weighing performance indicators using the analytical network process, the objective matrix method to measure performance assessment, and the traffic light system method to help identify critical indicators. According to the findings of the study, energy consumption is the most important factor that leads to GSCM application success in an Indonesian steel manufacturing company. The proportion of reusable materials is the smallest and most important performance metric that has to be improved. The suggested methodology may be used by steel company supply chain managers to assess and enhance GSCM performance. The suggested approach is verified by a case analysis at an Indonesian steel manufacturing company. Graphical
PubDate: 2022-06-22
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- Investigation of the Hydrogen-Rich Reduction of Panzhihua Ilmenite
Concentrate Pellets-
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Abstract: The hydrogen-rich reduction of ilmenite concentrates has a significant effect on the reduction of the carbon footprint of the titanium slag production process. This study investigates the hydrogen-rich reduction of Panzhihua ilmenite concentrate pellets. The pellets were roasted at 500, 700, 900, and 1100 °C and used as the raw material for the reduction process. The effects of the pellet roasting temperature, magnetite concentrate content of the pellets, reduction temperature, and reducing gas composition on the reduction process were experimentally studied. The results showed that the average reduction rate is affected by the phase and dense structure of the pellet, reduction temperature, and hydrogen content. Further, the reduction process can be accelerated by increasing the H2 content and reduction temperature. The high compressive strength of the pellet, owing to its dense inner structure, is not conducive for the reduction process. Moreover, studies show that the H2/CO ratio has negligible effects on the reduction mechanism. The reaction mechanism of the pellet reduction process is three-dimensional diffusion. Furthermore, the effect of the pellet phase on the hydrogen-rich reduction process has been discussed. Graphical
PubDate: 2022-06-17
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- Crystallization Characteristics and Properties of Glass Ceramics Derived
from Iron Tailing-
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Abstract: In this study, iron tailings were used as raw materials mixing with Al2O3, SiO2, and/or CaO sintered at 950–1400 °C to produce glass ceramics. In Al2O3/tailing and Al2O3/SiO2/tailing systems, the newly formed crystalline mullite (3Al2O3·2SiO2) reached its maximum content of 83.7 wt% for sample with Al2O3/SiO2/tailing mass ratio of 6/2/2. In Al2O3/SiO2/CaO/tailing system, the content of newly formed anorthite (CaAl2Si2O8) increased to the maximum of 72.9 wt% for sample with Al2O3/SiO2/CaO/tailing mass ratio of 7/8/4/6 sintered at 1450 °C. The properties of glass ceramic products were significantly improved in samples with high content of crystalline mullite or anorthite and low surface porosity. Obtained glass ceramic in Al2O3/SiO2/tailing system with mass ratio of 6/2/6 showed excellent properties of chemical resistance (99.99%), compressive strength (1061.6 MPa), and low water absorption (0.2%). The high performance of glass ceramics and low leachability of hazardous metals shed light on the potential application of iron tailings in building and decorative materials. Graphical
PubDate: 2022-06-17
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- Design and Fluidity Research of a New Tundish Flux for Rare Earth Steel
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Abstract: A new CaO–Al2O3–Ce2O3–MgO–SiO2 tundish flux for rare earth steel has been presented in the current study based on the phase diagram and iso-activity diagram. The effect of Ce2O3 content and w(CaO)/w(Al2O3) on the melting temperature, viscosity, and crystalline phase was investigated. Results indicated that with the increasing Ce2O3 content and w(CaO)/w(Al2O3), the viscosity and melting temperature decreased, whereas the breaking temperature exhibited the opposite tendency. When the Ce2O3 content increased from 5 to 9 wt%, the crystalline phase began to precipitate. The Ce2O3 content further increases to 17 wt%, the crystalline phase changed from CaCeAl3O7 to CaCeAl3O7 and CeAlO3. The crystalline phase changed from CaCeAl3O7 to Ca3Al2O6, CaCeAl3O7, and MgO as the w(CaO)/w(Al2O3) increased from 0.9 to 1.3. The best range of the compositions of the low-reactivity tundish flux was w(CaO)/w(Al2O3) = 1–1.3, MgO = 5 wt%, SiO2 = 5 wt%, Ce2O3 = 0–10 wt%. The melting temperature was in the range of 1300–1320 °C, and the viscosity at 1500 °C was in the range of 0.18–0.45 Pa·s. The compositions were suitable for the development of sustainable metallurgy. Graphical
PubDate: 2022-06-17
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- Synergetic Utilization of Zinc-Bearing Dust by Carbothermic
Reduction-Roasting Process: Phase Transformation and Morphological
Evolution-
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Abstract: An economic and effective strategy synchronously utilizing blast furnace bag dust (BF-BD) and converter-removing dust (C-RD) by carbothermic reduction roasting is reported to achieve separation and recovery of iron and zinc. In this paper, the effect of operating parameters on the recovery rate and remove rate of Fe and Zn from BD and GD was initially studied by synergetic carbothermic roasting reduction. The optimized parameters include a reduction temperature pf 1200 °C, a reduction time of 90 min, a FC/O of 2.0, and a proportion of C-RD/BF-BD of 7:3, and the removal efficiency of Zn and metallization degree of Fe reached 98.35% and 90.58%, respectively. The phase transformation and stepwise reduction behavior of wüstite (ZnO)x(FeO)1−x, spinel ZnxFe1−xAl2O4, olivine ZnxFe2−xSiO4, and gehlenite ZnzFe2−xSiAl2O7 are systematically investigated by SEM–EDS, XRD, TG/DTG, and thermodynamic analyses. It was found that the formation of wüstite (ZnO)x(FeO)1−x as an intermediates plays an crucial role in the formation of metallic Zn–Fe–C alloy. Phase transformation and reduction mechanisms of C-RD and BF-BD and the interfacial reaction formation mechanism of wüstite (ZnO)x(FeO)1−x were discussed and clarified in synergistic carbothermic reduction process. Graphical
PubDate: 2022-06-15
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- Sustainable Applications for Disposal of Recycled Aluminum: A Systematic
Literature Review Using the SciMAT Software-
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Abstract: This review aims to carry out a scientific review of the current status of aluminum can recycling processes over the last 15 years, seeking to find sustainable applications for its destination. Thus, the research topics were defined by the identification of the structure of the scientific field of research and the relationship of aluminum recycling, casting processes, and formation of aluminum-based alloys, as well as their applications. Therefore, three topics were studied: the state of the art of aluminum recycling practices; processes being performed and aluminum casting techniques and methods; and the current state of formation of secondary aluminum-based alloys, the alloy elements being used, and their applications after the formation of alloys. Based on the above three topics, the research topics include (A) aluminum recycling, (B) casting processes, and (C) the formation of aluminum-based alloys and their applications. For bibliometric analysis, the software SciMAT was applied. Through the overlaid map and the evolution map, it was possible to detect the temporal evolution of the scientific field in the researched area. Cluster analysis allowed us to identify the motor words. Through the connections network, keywords connected to the motor themes were verified that indicated the connection areas of the research field and the main authors. The simulation models were factors of innovation in the area, as well as the software packages ANSYS and ProCAST. In the area of alloy formation, the liquid metal cleaning analyzer technique was highlighted in the production of high-quality alloys. The important connections to aluminum recycling feasibility are presented in this review. Graphical
PubDate: 2022-06-13
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- Efficient Utilization of Carbon-Bearing Dusts in Composite Agglomeration
Process for Iron Ore Sintering-
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Abstract: This study focused on improving recycling of carbon-bearing dusts from integrated steel plants by the composite agglomeration process (CAP), in which four types of the dusts were prepared as pelletized feed, while the other raw materials were used as matrix feed for sintering to produce agglomeration product as a substitute for traditional iron ore sinter. It was found that the carbon distribution in the pelletized feed and matrix feed and segregation of pelletized feed in the burden layer strongly affected the process. When the total carbon content of the feeds was 3.22 wt%, the proper carbon content ratio of pelletized feed to matrix feed was 1.65–2.48. At this moment, optimizing the segregation of pelletized feed which contained 6.64 wt% carbon (named DP-4) in the sintering burden layer would improve the quality indexes of agglomeration product with higher carbon utilization efficiency, i.e., lower total carbon consumption. Graphical
PubDate: 2022-06-10
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- Leaching Behavior of Scandium from Limonitic Laterite Ores Under Sulfation
Roasting–Water Leaching-
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Abstract: In the present study, the leaching behavior of scandium from limonitic laterites under sulfation roasting–water leaching (SAL) was explored. The mineralogical analysis of limonitic laterites showed that scandium was associated with the iron phase. The roasting temperature played an important role in the iron phase conversion during the sulfation roasting process. With an increase in the roasting temperature from 100 to 800 °C, the iron phase (goethite, magnetite, and hematite) gradually converted to monoclinic Fe2(SO4)3 (400 °C), then to rhombohedral Fe2(SO4)3 (600 °C), and finally to hematite (800 °C). Due to the iron phase conversion mechanism, the leaching efficiency of scandium gradually increased first and then decreased with the increase of roasting temperature from 100 to 800 °C. When limonitic laterites roasted at temperature of 600 °C for 2 h with sulfuric acid/laterite ratio of 1/4 (mL/g), a total of 81.15% of scandium and only 0.37% of iron were extracted into leaching solution at 30 °C with the liquid-to-solid ratio of 4:1 (mL/g) for 1 h with agitation. The SAL process enables the selective and efficient enrichment of scandium from low-grade limonitic laterites with lower costs for equipment and operation compared to high-pressure acid leaching (HPAL), lower acid consumption, and lower dissolution of iron compared to atmospheric pressure acid leaching (AL). Graphical
PubDate: 2022-06-10
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- Transforming a Carbon Rich Metallurgical Residue from a Sponge Iron
Production into a Hydraulic Binder-
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Abstract: This paper explores the possibility to convert a metallurgical residue from a sponge iron production (MR) with approximately 20 wt% amorphous carbon into a hydraulic binder. The challenge lies in developing an industrially-realistic, simple and robust process that exploits the characteristics of the residue, instead of trying to introduce the residue in an existing process. In the first stage the goal was to direct the chemistry of MR towards a “classical” ordinary Portland cement (OPC) clinker composition, while in the second stage the goal was to develop a process in which the carbon from the mixture would be used as a fuel to reach the desired temperature. Lab scale experiments have shown that the heat treated MR with 37 wt% CaCO3 contained, among others, all four cement clinker phases (i.e. C2S, C3S, C4AF and C3A). Upscaling experiments by means of sintering pan have further proven that such a material could be sintered in large quantities, while the energy from C burning was sufficient to achieve the required sintering temperature range (1000 – 1300 °C). The produced material consisted mainly of β-C2S, C3S, C4AF and C3A, and reached 28th day compressive strength of 28 MPa. This value is somehow lower than that of CEM I 32.5 N, yet the binder can be used in low- or non-load bearing applications. Graphical
PubDate: 2022-06-07
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- Chromium Stabilization in Ferrochromium Slag for its Utilization as
Aggregate Material-
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Abstract: Ferrochromium slag is a by-product of ferrochromium production via the smelting of chromite ores. The mechanical properties of this slag make it a potential material to be used as an inexpensive construction material, the utilization of which can reduce the use of natural resources. Despite its potential use, ferrochromium slag is treated as a waste due to environmental and health concerns regarding the leaching of its heavy metal content, the most concerning of which is carcinogenic chromium (VI). Research has shown that the spinel phase in ferrochromium slag stabilizes chromium by trapping it in the spinel structure and preventing its leaching to the environment. This study investigates the effect of heat treatment and composition change on spinel formation in ferrochromium slag and subsequently on the stabilization of chromium. Slag samples of the MgO–Al2O3–SiO2–CaO–FeO–Cr2O3 system were synthesized at 1650 °C for 10 h in a vertical tube furnace. Samples were heat treated after synthesis by holding them at 1400, 1475, and 1550 °C for 12 h before quenching. Leaching tests on heat-treated slag samples reveal that samples held at 1400 °C have the lowest chromium leachability. With a holding temperature of 1400 °C, slag samples were prepared with variations in Al2O3 content in the range of 0–20%. Higher Cr leaching is observed from samples as the Al2O3 content increases. Similar heat-treated samples were prepared with constant Al2O3 content and basicity (CaO/SiO2) varying from 0.3 to 0.7. An increase in basicity increases the amount of Cr released from the samples during leaching experiments. Graphical
PubDate: 2022-06-03
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- Recovery of Cu and Ni in Electroplating Sludge by a Low-Temperature
Alkaline Smelting Technique-
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Abstract: Serious concerns have been raised from the solid waste processing field about minimizing the environmental footprint of electroplating sludge (ES), not only because of its hazardousness but also due to the rising demand for recycling non-renewable metal resources. A low-temperature alkaline matte smelting process is proposed in the present study. Na2CO3 was used as a flux reagent for smelting ES at 1250 °C, which is 100–250 °C lower than those previously reported. XRD and SEM–EDS revealed that the presence of Na species in the matte and slag phases was conducive to reducing the smelting temperature. The relationship between the processing parameters, i.e., Na2CO3, coal powder, and sulfur dosages, and the partitioning of Cu, Ni, and Cr were investigated for optimal metal recovery. A copper–nickel matte (Cu + Ni = 46.9 wt%) was produced. Cu and Ni recovery achieved 95% and 90%, respectively, while over 99% Cr was concentrated in the slag. The TCLP test indicated that heavy metal leaching toxicities of the slag were below the Chinese national identification standards (GB5085.3-2007) due to the formation of stable spinel phases and embedment of heavy metals in the glassy slag matrix. Graphical
PubDate: 2022-06-02
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- Kinetic Investigation of Initial Oxidative Dissolution of Pyrite in
Alkaline Media (pH 9–12) and Influence of Ca and Mg: A Fundamental Study
for Pyrite Depression in Froth Flotation-
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Abstract: Froth flotation is a common mineral processing technique that is used to remove low economic gangue minerals, such as pyrite, from ore. The main hydrophilization mechanism on the pyrite surface is explained by the formation of hydrophilic iron (Fe) hydroxide and its complexation with calcium (Ca) and magnesium (Mg) ions; however, few quantitative results are available to determine the best physico-chemical condition to depress pyrite floatability. Fe-hydroxide formation, i.e., oxidative dissolution on a pyrite surface, is a kinetically control reaction; thus, this study investigated the short-term pyrite oxidation rate (~ 360 min) and the influence of the copresence of Ca and Mg under alkaline pH conditions (9, 10.5, and 12) as a fundamental study to establish optimal flotation and/or pre-treatment conditions for pyrite depression. The oxidative dissolution rates of pyrite increased after 120–150 min of reaction compared with the first reaction time: the rate constant (log k) increased from − 10.08 to − 9.5 in the absence of Ca and Mg. X-ray photoelectron spectroscopy analysis results showed that the formation of Fe1−xS2 became the dominant reaction in the first reaction stage; thereafter, S–S bond cleavage in the second reaction stage resulted in the acceleration of pyrite decomposition. Smaller rate constants resulted for the Ca and Mg solutions because of the formation of Ca and Mg hydroxides under alkaline conditions. However, this decrease in oxidation rate could influence the pyrite surface hydrophilization less, and hydrophilization has become the main reason for pyrite depression enhancement. Graphical
PubDate: 2022-06-01
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- Characterization and In Situ Abatement of SOx, NOx, and PCDD/Fs in Iron
Ore Sinter Machine Wind Legs-
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Abstract: It was observed that the oxides of sulfur and nitrogen (SOx and NOx), in large concentrations, were getting released from certain wind boxes of the sinter machine. The deposits in the wind legs were characterized and particulates with spherical, cubical, needle, and bar-like morphologies containing K, Na, and Cl were noticed. Nitrogen-based solids were found in clutter-like morphology. Some particles had a mixture of the above, SOx and NOx. These deposits were dissolved at room temperature in the solutions of sodium bicarbonate, urea, and di-sodium borate deca-hydrate (borax) in water to estimate the absorbance of K, Na, Cl, Ca, Mg, S, and N-based compounds. The solution of sodium bicarbonate did not capture NOx. SOx and NOx were not present in the filtrates of urea and borax. A solution of sodium bicarbonate in water 1% v/v was sprayed into a wind box and found that SOx had got reduced by 90% and NOx by about 55%. To maximize the capture of SOx and NOx, the solution was optimized at 2% v/v and found that both SOx and NOx had got reduced by 90%. A deposit from the electrostatic precipitator (ESP) was dissolved in acetone, hexane, and toluene and found that polychlorinated dibenzo para-dioxins and polychlorinated dibenzofurans (PCDD/Fs) have got broken down. Injecting nitrogen where PCDD/Fs are released is also suggested as an economical solution. Graphical
PubDate: 2022-06-01
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- Integrated Utilization of Vanadium-Titanium Magnetite Tailings for
Synthesis of Lightweight Foamed Ceramics: Effect of Chemical Composition
on the Properties and Phase Evolution-
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Abstract: Lightweight foamed ceramics were prepared using 55 wt.% vanadium-titanium magnetite tailings (VTMT) followed by sintering at 1130 °C. In the CaO-MgO-SiO2-Al2O3 foamed ceramic quaternary system, the CaO and SiO2 components play an important role in adjusting material properties and controlling phase transition. In this work, the effect of SiO2 and CaO content as additives on the tailings-based foamed ceramics properties, phase evolution, pore structure, and microstructure were systematically investigated. The results revealed that the bulk density of the samples increased with increasing CaO content. A small amount of CaO content accelerated the foaming of the samples but higher CaO contents (more than 2 wt.%) inhibited bubble growth by an increased formation of diopside (CaMgSi2O6) and other crystals with high melting temperature. Meanwhile, the amount of diopside increased from 33.56 wt.% to 74.68 wt.% with increasing CaO content, as determined by Rietveld refinement. The excessive addition of SiO2 negatively affected the number of pores, reduced pore interconnectivity, and resulted in lower average pore sizes. Moreover, samples with excessive SiO2 also displayed higher bulk density and lower open porosity. This study provides an important reference for the regulation of major chemical components for preparing solid waste-based foamed ceramics. Graphical
PubDate: 2022-06-01
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- One-Step Solvometallurgical Process for Purification of Lithium Chloride
to Battery Grade-
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Abstract: The use of lithium in manufacturing of lithium-ion batteries for hybrid and electric vehicles, along with stringent environmental regulations, have strongly increased the need for its sustainable production and recycling. The required purity of lithium compounds used for the production of battery components is very high (> 99.5%). In this work, a solvometallurgical process that exploits the differences in solubility between LiCl and other alkali and alkaline-earth chlorides and hydroxides in ethanolic solutions has been investigated for the purification of LiCl to battery grade at room temperature. A closed-loop flowsheet based on the green solvent ethanol is proposed for purification of LiCl, a precursor for battery-grade LiOH·H2O. High-purity LiCl solution (> 99.5% Li) could be obtained in a single-process step comprising the simultaneous selective dissolution of LiCl and the precipitation of Mg(OH)2 and Ca(OH)2 using LiOH·H2O in 95 vol% ethanol. However, the analogous process in aqueous solution resulted in impure LiCl (typically less than about 75%). Graphical
PubDate: 2022-05-23
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- Steelmaking Slag as a Valuable Industrial Waste in the Preparation of
5-Substituted-1H-Tetrazoles on Water-
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Abstract: The steelmaking slag (SMS) is a by-product of steelmaking factories and a valuable industrial waste, which is a heterogeneous mixture of some common metal oxides such as SiO2, Al2O3, Fe2O3, CaO, and MgO. The SMS is a readily available, non-toxic, environmentally friendly, thermally stable, and reusable magnetic heterogeneous catalyst that can be easily handled and it showed a good magneto-catalytic performance. In this work, a successful and versatile water preparation of 5-substituted-1H-tetrazoles in the presence of steelmaking slag as a catalyst is reported via click reaction. A series of aliphatic and aromatic nitriles underwent via [3 + 2] cycloaddition reaction with sodium azide under standard conditions to afford a diverse array of 5-substituted-1H-tetrazoles in good to excellent yields. The reactions occur at almost low reaction times, with no need of inert reaction conditions and avoids usage or formation of any potentially toxic or explosive chemicals. The SMS catalyst was characterized by FT-IR spectroscopy, powder X-ray diffraction, energy‐dispersive X‐ray mapping and scanning electron microscopy, and X-ray fluorescence techniques. Moreover, the procedure is simple, cost effective, and reliable that holds potential for further applications in organic syntheses and industrial requirements. Graphical
PubDate: 2022-05-23
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- Alternative Method for Treating Electric Arc Furnace Dust: Simulation and
Life Cycle Assessment-
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Abstract: The technical and environmental aspects of treating electric arc furnace dust (EAFD) using a novel process including alkaline roasting and organic acid leaching were evaluated and compared to the globally applied conventional Waelz process. The global warming potentials of the roasting–organic acid leaching process (with co-product credits) and the Waelz processes were 7.48 and 4.71 kg CO2-eq with 33% Zn dust as the feed material. However, with decreasing Zn content, the novel process become environmentally more competitive, and with 12% Zn, the corresponding GWP values were 6.31 and 9.26 kg CO2-eq. Co-product recovery decreased the net environmental impacts from the processing of the dust, which gave some benefits to the novel process. The Waelz process was observed to be energy intensive; however, the high consumption of leaching and roasting chemicals was the issue in the novel process. The excess caustic soda in the roasting step was observed to be a significant factor in the overconsumption of the organic acid in the leaching stage, and therefore, optimization of the roasting step is crucial. Other ways to decrease leaching chemical consumption include investigating the possibility to reuse the raffinate in leaching, or scrubbing the leach calcine from acid-consuming alkali. Evaluating the impacts of novel processes early enables iterative and agile process development and the directing the focus on the problem areas. Graphical
PubDate: 2022-05-23
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- Correction to: Analysis of the Theoretical and Practical Energy
Requirements to Produce Iron and Steel, with Summary Equations that Can Be
Applied in Developing Future Energy Scenarios-
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PubDate: 2022-05-13
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- Wettable TiB2 Cathode for Aluminum Electrolysis: A Review
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Abstract: Titanium diboride (TiB2) is considered a promising material for wettable cathodes in aluminum electrolysis. The demand for wettable cathodes is associated with the development of inert anode technologies to eliminate CO2 emissions caused by the conventional aluminum reduction process. Titanium diboride has been given special attention due to its superior properties, such as high wettability, good electrical conductivity, wear resistance, and excellent chemical stability. In this paper, we discuss different synthesis techniques used for the preparation of TiB2 cathode material. The main methods are sintering, electrodeposition, and plasma spraying. Electrodeposition is considered to be the most reliable low-cost method for TiB2 preparation. The vertical anode–cathode distance can be reduced by introducing wetted TiB2 cathodes, through which specific energy consumption can be reduced significantly. For a longer lifetime, the TiB2 cathodes should be resistant to electrolyte penetration. Further research should be conducted to understand the electrochemical behavior of TiB2 in low-temperature electrolytes. Graphical
PubDate: 2022-05-02
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- Hydrometallurgical Recovery of Manganese from Ferruginous Manganese Ore by
Reductive-Acid Leaching with Sodium Dithionite-
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Abstract: The leaching behavior of manganese from ferruginous manganese ore in sulphuric acid solution using sodium dithionite as a reducing agent was investigated. The optimum sulphuric acid concentration, leaching time, temperature, pulp density and agitation speed for leaching of manganese was determined. Complete manganese leaching was observed under the optimized conditions of 0.6 M H2SO4, 0.49 M sodium dithionite, 200 g/L pulp density, 60 °C leaching temperature, 600 rpm stirring rate and 120 min reaction time. The leaching kinetics and dissolution process have also been analyzed by model fitting and microstructural observation. The kinetics of reductive leaching of manganese ores by sodium dithionite in dilute sulphuric acid did not follow a shrinking core kinetic model. The Avrami model was used successfully to explain the kinetic data. The positive values of both ∆H and ∆S indicates that the leaching process is endothermic and random while the negative values of ∆G indicate that manganese dissolution process is spontaneous in nature. After removal of impurities from the leach solution by precipitation, a high purity (99.2%) α-Mn2O3 was synthesized from the concentrated Mn solution. The as-synthesized manganese oxide powder was characterized by chemical analysis, SEM–EDS and XRD analysis. The present process would be a key technology for reductive leaching of manganese oxide ores in an economical and efficient way. Graphical
PubDate: 2022-04-25
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