Article
Materials Science, Multidisciplinary
Xuewei Yang, Xin Chen, Tingan Zhang, Jiayuan Ye, Guozhi Lv, Jinshan Zhang
Summary: This paper briefly describes the characteristics and current problems of red mud, as well as the progress in research on iron extraction from high-iron red mud. By adding conditioning materials and quenching and tempering, iron tailings extracted from red mud were reconstructed to form molten tailings in the laboratory. Thermodynamic analysis and experimental verification were conducted to determine the optimal conditions for iron extraction by calcified slag reduction. The extracted iron tailings met the expected composition standard and consisted mainly of C(2)AS and CT phases.
Article
Engineering, Chemical
Jianwen Yu, Yanfeng Li, Yang Lv, Yuexin Han, Peng Gao
Summary: An innovative suspension magnetization roasting followed by magnetic separation process was developed to recover iron from high-iron red mud. Under the optimized conditions, an iron concentrate with high purity and recovery rate was obtained. The suspension magnetization roasting converted hematite into magnetite, improving the magnetism, and also allowed hematite and alumina to enter the iron concentrate, increasing the aluminum content.
MINERALS ENGINEERING
(2022)
Review
Energy & Fuels
Hao Kong, Tuo Zhou, Xinhua Yang, Yingli Gong, Man Zhang, Hairui Yang
Summary: This paper reviews the methods of iron recovery from red mud, including physical, chemical, and emerging recovery methods. Comparing these processes, it is concluded that fluidized bed reduction is a promising process, but further research is needed to overcome technical difficulties.
Article
Thermodynamics
Rakesh Kumar, Thomas C. Alex
Summary: This paper focuses on the carbothermic reduction of red mud in the presence of sodium carbonate. The research investigates the phase equilibrium, thermal analysis, and roasting and leaching processes of red mud-soda-carbon pellets. The study reveals the interdependence of the decomposition of sodium carbonate, metallisation of red mud, sodium aluminate formation, and alumina recovery.
JOURNAL OF THERMAL ANALYSIS AND CALORIMETRY
(2023)
Article
Engineering, Chemical
Junying Wan, Tiejun Chen, Xianlin Zhou, Yanhong Luo, Wei Liu, Qicai Lu
Summary: The study found that the addition of high-manganese iron ore can promote the direct reduction process of high-iron red mud and increase the metallization rate.
MINERALS ENGINEERING
(2021)
Review
Engineering, Environmental
Xiao Liu, Yuexin Han, Fayu He, Peng Gao, Shuai Yuan
Summary: This paper systematically reviews the iron recovery methods for high-iron RM, dividing them into physical separation, pyrometallurgy (reduction smelting and reduction roasting), and hydrometallurgy (acid leaching). The basic principles and effects of these technologies are summarized, as well as the advantages and disadvantages. Feasibility and economic cost are identified as main factors restricting industrial application.
JOURNAL OF HAZARDOUS MATERIALS
(2021)
Article
Green & Sustainable Science & Technology
Xiao Zhou, Guihua Liu, Tiangui Qi, Jiasheng Zhao, Zhihong Peng, Yilin Wang, Leiting Shen
Summary: The surface magnetization technique can improve the efficiency of iron recovery from high-iron red mud. Increasing the temperature and NaOH concentration can enhance the iron recovery, while prolonging magnetization time has a negative effect. Coarse particles in the red mud contribute to higher iron recovery and total iron content in the concentrate.
JOURNAL OF SUSTAINABLE METALLURGY
(2023)
Article
Chemistry, Applied
Junhui Xiao, Kai Zou, Nanlan Zhong, Deqiang Gao
Summary: In this study, the separation of iron and scandium from Sc-bearing red mud was investigated. The red mud contained 31.11 wt% total iron (TFe), 0.0045 wt% Sc, and hematite and ferrosilite as the main Fe-bearing minerals. By applying a novel deep reduction roasting and magnetic separation process with the addition of coke and CaO, iron was extracted and scandium was enriched from the Sc-bearing red mud. The test results showed high Fe recovery of 92.96% and Sc recovery of 98.65%.
JOURNAL OF RARE EARTHS
(2023)
Article
Green & Sustainable Science & Technology
Pavel Grudinsky, Dmitry Zinoveev, Anfisa Yurtaeva, Alex Kondratiev, Valery Dyubanov, Alexander Petelin
Summary: This study investigated the carbothermic roasting of red mud followed by dry or wet magnetic separation with the addition of alkaline salts to enhance iron extraction. Sodium and potassium carbonates and sulfates were compared for their effects on iron recovery, and the influence of roasting temperature and additives on iron concentrate grade was studied. The addition of these salts during carbothermic roasting improved magnetic separation of metallic iron, as confirmed by the analysis of composition and microstructure of the separation products.
JOURNAL OF SUSTAINABLE METALLURGY
(2021)
Article
Environmental Sciences
Xiaofei Li, Ting-An Zhang, Kun Wang, Guozhi Lv, Xi Chao, Xuewei Yang
Summary: This study verifies the advantages of vortex melting reduction treatment for red mud and provides an experimental basis for its harmless and high-value utilization.
BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY
(2022)
Article
Green & Sustainable Science & Technology
Shrey Agrawal, Nikhil Dhawan
Summary: This study focuses on the hydrogen reduction of red mud and subsequent acid leaching to recover valuable elements. The results show that reduction at 450°C for 30 minutes yields 10% metallization of magnetite, while increasing the temperature to 900°C results in 97% metallization of metallic iron. The hydrogen-reduced products at 900°C can be used for efficient extraction of iron, gallium, and scandium. Rating: 8/10
JOURNAL OF SUSTAINABLE METALLURGY
(2023)
Article
Environmental Sciences
Heming Wang, Yiyong Wang, Hui Jin, Jidong Li, Xiaomin Wang
Summary: This article focuses on the hydrothermal reduction behavior of the iron ore phase in the comprehensive utilization of red mud. The results showed that using starch as the reducing agent can effectively separate and recover sodium, aluminum, and iron from high-iron red mud.
BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY
(2022)
Article
Construction & Building Technology
Ashutosh Singh Raghubanshi, Manish Mudgal, Anil Kumar, R. K. Chouhan, Avanish Kumar Srivastava
Summary: The recycling and large stockpile of red mud have raised social and environmental concerns, leading to the development of a process for the bulk utilization of red mud into heavyweight aggregate. By investigating the in-situ growth of high-density ceramics and material properties, a heavyweight aggregate with lower water absorption and abrasion value was developed to meet relevant standards.
CONSTRUCTION AND BUILDING MATERIALS
(2021)
Article
Green & Sustainable Science & Technology
Rita Khanna, Yuri Konyukhov, Dmitry Zinoveev, Kalidoss Jayasankar, Igor Burmistrov, Maksim Kravchenko, Partha S. Mukherjee
Summary: Managing red mud is a serious environmental issue, as it is a solid waste byproduct of the alumina recovery process. This study assessed the potential of using red mud as a low-grade iron resource and reviewed its utilization in commercial and industrial operations.
Article
Materials Science, Ceramics
Zheng Chen, Wanying Wu, Nan Chen, Diyun Chen, Minhua Su
Summary: A low thermal stabilization process was designed to stabilize U(VI) in red mud into geopolymer-like microstructures, offering a promising strategy for the elimination and stabilization of U(VI) from waste streams.
CERAMICS INTERNATIONAL
(2022)
Article
Green & Sustainable Science & Technology
Peng Wu, Guihua Liu, Xiaobin Li, Zhihong Peng, Qiusheng Zhou, Tiangui Qi, Yilin Wang, Leiting Shen
Summary: This study investigated the feasibility of removing organics through foam flotation in synthetic Bayer liquor and verified its effectiveness in industrial production. Low molecular weight organics showed higher removal rates in the solution, while elevated temperatures reduced their removal rates. The enrichment of organics in the foam was mainly attributed to small bubbles, high TOC concentrations, and multilayer adsorption.
JOURNAL OF CLEANER PRODUCTION
(2022)
Article
Chemistry, Multidisciplinary
Guotao Zhou, Yilin Wang, Tiangui Qi, Qiusheng Zhou, Guihua Liu, Zhihong Peng, Xiaobin Li
Summary: The conversion of Al-substituted goethite to hematite in gibbsitic bauxite was investigated in this study. The results showed that the synthetic Al-goethite started converting to hematite at around 280 degrees C, while the natural Al-goethite started converting at around 320 degrees C. The addition of NaOH accelerated the conversion process. The converted hematite inherited the needle-like appearance of the original Al-goethite and had a porous structure. Digestion experiments confirmed that low-temperature roasting-Bayer digestion significantly improved alumina recovery and resulted in iron-rich red mud that can be easily co-processed in the steel industry, which could lead to significant emission reduction.
Article
Chemistry, Multidisciplinary
Guoyu Wu, Guihua Liu, Xiaobin Li, Zhihong Peng, Qiusheng Zhou, Tiangui Qi
Summary: Fine activated alumina (FAA) with a high specific surface area and open mesoporous structure was synthesized for phosphate adsorption. FAA exhibited a high adsorption capacity for phosphate, mainly through physical adsorption, and could be easily regenerated.
Article
Green & Sustainable Science & Technology
Luwei Cheng, Yilin Wang, Biao Wang, Tiangui Qi, Guihua Liu, Qiusheng Zhou, Zhihong Peng, Xiaobin Li
Summary: This study investigated the mechanism of mineral phase transformation during red mud dealkalization, finding that the reaction temperature and molar ratio of CaO to Na2O have a significant impact on the phase changes of desilication products.
JOURNAL OF SUSTAINABLE METALLURGY
(2022)
Article
Environmental Sciences
Guotao Zhou, Yilin Wang, Tiangui Qi, Qiusheng Zhou, Guihua Liu, Zhihong Peng, Xiaobin Li
Summary: The hydrothermal hydrogen reduction process for high-iron bauxite residue (red mud) was studied to investigate the optimal conditions for alumina extraction and iron mineral enrichment. The results showed that hydrogen reduction accelerated the conversion from Al-goethite to hematite and/or magnetite, leading to the enrichment of iron content in the residue. The alumina recovery ratio reached 95.40% and the iron grade in the residue was enriched to 55.85% after hydrothermal hydrogen reduction. Co-processing the obtained iron-rich residue in the steel industry could significantly decrease the discharge of red mud.
BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY
(2022)
Article
Green & Sustainable Science & Technology
Xiao-bin Li, Peng Wang, Hong-yang Wang, Qiu-sheng Zhou, Tian-gui Qi, Gui-hua Liu, Zhi-hong Peng, Yi-lin Wang, Lei-ting Shen
Summary: A novel technology for extracting alumina from high-alumina coal gangue (HACG) has been proposed in this study, which utilizes a roasting-alkaline leaching-Bayer digestion process. The study has successfully resolved the issue of silica resource utilization. The results show that through reductively roasting the mixture of HACG and hematite, the main mineral kaolinite in the HACG can be converted into silica solid solutions and alumina, allowing for efficient separation of silica and alumina.
JOURNAL OF SUSTAINABLE METALLURGY
(2022)
Article
Chemistry, Physical
Peng Wu, Guihua Liu, Xiaobin Li, Zhihong Peng, Qiusheng Zhou, Tiangui Qi, Yilin Wang, Leiting Shen, Hui Fang, Yonglin Wang
Summary: Effective enrichment of organics by foam flotation is an important method for removing organics from Bayer liquor. This study investigated the effect of sodium laurate and sodium stearate on the removal efficiency. The results showed that the removal efficiency increased with the concentration of these surfactants. The addition of sodium palmitate and sodium oleate also affected the interfacial structure and the size of micelles, leading to enhanced removal efficiency.
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Engineering, Chemical
Saikui Wang, Yilin Wang, Tiangui Qi, Guihua Liu, Qiusheng Zhou, Zhihong Peng, Fei Niu, Xiaobin Li
Summary: This study focuses on the effects of oxidant and reductant on the reaction extents of pyrite with sodium aluminate solution at elevated temperatures. The presence of oxidant forms a dense layer on the surface of unreacted pyrite, inhibiting its reaction. On the other hand, the presence of reductant promotes the decomposition of pyrite and the formation of a chemical etching channel. Experimental results show that the inhibition of pyrite reaction by oxidant addition is affected by the organic content of the bauxite. These findings may facilitate the direct treatment of high-sulfur diasporic bauxite for alumina production using the Bayer process without desulfurization pretreatment.
MINERALS ENGINEERING
(2023)
Article
Chemistry, Physical
Chuanyin Xiong, Qi Yang, Weihua Dang, Qiusheng Zhou, Xue Jiang, Xuhui Sun, Zequn Wang, Meng An, Yonghao Ni
Summary: In this study, a multi-functional paper-based supercapacitor (APC-PVA@ZnCl2) with excellent temperature adaptability, plasticity, tensile strength, strong adhesion, and self-healing properties was developed by introducing PVA and ZnCl2 into carbonized paper-based materials. The APC-PVA@ZnCl2 supercapacitor exhibited high adaptability to the environment, maintaining a high volumetric specific capacitance of 3438.45 mF cm(-3) and high volumetric specific energy density of 44 mW h cm(-3) even in a low-temperature environment below zero. Additionally, the APC-PVA@ZnCl2 composite showed good tensile properties, can function as a sensing material, and displayed outstanding thermoelectric properties.
JOURNAL OF MATERIALS CHEMISTRY A
(2023)
Article
Green & Sustainable Science & Technology
Guo-tao Zhou, Yi-lin Wang, Yu-guan Zhang, Tian-gui Qi, Qiu-sheng Zhou, Gui-hua Liu, Xiao-bin Li
Summary: This study proposed a clean two-stage Bayer digestion technology to obtain iron-rich red mud from high-iron gibbsitic bauxite processing. The digestion conditions were systematically studied, and the results showed high Al2O3 extraction rate and iron enrichment degree in red mud. The research will contribute to the green and sustainable development of the alumina industry by reducing the discharge of red mud through value-added use.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Engineering, Environmental
Xiaobing Gao, Qiusheng Zhou, Yilin Wang, Tiangui Qi, Leiting Shen, Guihua Liu, Zhihong Peng, Xiaobin Li
Summary: In order to separate and utilize alumina and silica in aluminosilicate solid wastes effectively, the structures and properties of high-modulus sodium silicate solutions were studied under different conditions. It was found that the polymerization degree and viscosity of the solution increased with higher modulus, resulting in a more complex solution structure. The number of high-polymeric siloxy groups also increased with temperature, but the temperature and residence time did not promote their polymerization. The sodium oxide concentration had a positive effect on the polymerization degree and number of silicate species. Furthermore, the viscosity of high-modulus solutions increased significantly due to the presence of higher-polymeric siloxy groups, while the pH change was not significant.
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
(2023)
Article
Green & Sustainable Science & Technology
Changda Zhang, Qiusheng Zhou, Yilin Wang, Leiting Shen, Tiangui Qi, Guihua Liu, Zhihong Peng, Xiaobin Li
Summary: This study proposes a novel and sustainable process for separating and recovering vanadium from Bayer vanadium sludge, through phosphate removal by CaCO3, vanadium precipitation by BaCO3, and NH4HCO3 leaching. The process achieves high efficiency and environmental friendliness, saving costs and avoiding effluent pollution.
JOURNAL OF CLEANER PRODUCTION
(2023)
Article
Chemistry, Physical
Qiusheng Zhou, Yuan Tian, Mingyuan Wang, Shuangying Lei, Chuanyin Xiong
Summary: A molten salt-assisted strategy was developed to anchor transition metal-based active sites into porous carbon nanosheets, resulting in chitosan-based nitrogen-doped nanosheets decorated with CoNx. The synergistic effect between CoNx and nitrogen-doped carbon nanosheets significantly accelerates the sluggish reaction kinetics of oxygen reduction and oxygen evolution. The Zn-air batteries equipped with CoNx/CPCN-900 as the air electrode exhibit outstanding durability, high power density, and high gravimetric energy density. Furthermore, the assembled all-solid cell demonstrates exceptional flexibility and power density.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2023)
Article
Metallurgy & Metallurgical Engineering
Qiu-sheng Zhou, Li-juan Xiang, Qing-ping Huang, Xiang-ming Xu, Xiao-bin Li, Li-qun Yang
Summary: The current production of ammonium paratungstate tetrahydrate faces challenges such as long process, high energy consumption, low tungsten crystallization ratio, and environmental pollution. This study aims to develop a sustainable technology for direct production of ammonium paratungstate tetrahydrate. The results demonstrate that tungsten trioxide monohydrate can react stoichiometrically with ammonium bicarbonate or ammonium carbonate through a direct transformation reaction under different experimental conditions. By adding solid tungsten trioxide monohydrate and 80x10(-6) g/L PEG2000 into an ammonium bicarbonate solution with a liquid-to-solid mass ratio of 2 at 80 degrees C for 3 hours, dense-surface ammonium paratungstate tetrahydrate with an average particle size of 61.7 μm was successfully prepared. The transformed ammonium paratungstate tetrahydrate meets the chemical purity standards of APT center dot 4H(2)O-0 grade.
JOURNAL OF CENTRAL SOUTH UNIVERSITY
(2023)
Article
Engineering, Environmental
Dongsheng Wang, Haixia Wang, Li Luo, Qiusheng Zhou, Xiaoqing Qiu
Summary: In this study, red mud was demonstrated to be a valuable resource for fabricating efficient catalysts for the hydrogenation of p-nitrobenzene compounds. The pyrolysis of reed effectively promoted the reduction of hematite (Fe2O3) in red mud into magnetite (Fe3O4). The as-obtained catalysts contained vast basic groups inherited from red mud, facilitating the adsorption and ionization of p-nitrobenzene compounds. The magnetic Fe3O4 components catalyzed the hydrolysis of NaBH4 to produce active hydrogen species, resulting in the hydrogenation of nitro to amino group under ambient conditions. Thus, this work provides a new strategy of trash to treasure by designing and developing red mud-based functional materials.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
