Article
Engineering, Chemical
Bin Ji, Alex Xia, Wencai Zhang
Summary: Florencite-(Ce) was synthesized and its thermal phase transformation behavior was investigated. Results showed that the decomposition and recrystallization of Florencite-(Ce) occurred at different temperature ranges, and the gradual decomposition of florencite led to an increase in the solubility of Ce. The phase transformation of Florencite-(Ce) was found to be an independent reaction from the presence of kaolinite and coal coarse refuse.
Article
Engineering, Environmental
Siiri Peramaki, Antti Tiihonen, Joona Rajahalme, Sylva Larsson, Elmeri Lahtinen, Joni Niskanen, Roshan Budhathoki, Ari Vaisanen
Summary: An efficient leaching process has been developed for extracting nickel, cobalt, and rare earth elements (REEs) from spent nickel metal hydride (NiMH) battery waste. This process involves dry chlorination followed by water leaching, and it has shown high metal recovery rates and environmental friendliness, making it a potential alternative to traditional mineral acid leaching.
JOURNAL OF ENVIRONMENTAL CHEMICAL ENGINEERING
(2022)
Article
Environmental Sciences
Sabrina F. Lutke, Marcos L. S. Oliveira, Samuel R. Waechter, Luis F. O. Silva, Tito R. S. Cadaval, Fabio A. Duarte, Guilherme L. Dotto
Summary: This study investigates the leaching conditions and mechanisms of rare earth elements (REE) from phosphogypsum (PG). Through experimental design and optimization, high leaching efficiency values were obtained using sulfuric acid at a concentration of 2.9 mol L-1, a solid/liquid ratio of 1.7/20 g mL(-1), and a temperature of 55 C. The leaching kinetics results indicated that most REE reached equilibrium in about 20 minutes, and the mechanism investigation suggested that surface chemical reaction and diffusion through the boundary layer controlled the leaching process.
Article
Chemistry, Applied
Wanli Yi, Xuefeng She, Huai Zhang, Zhenlong An, Jingsong Wang, Qingguo Xue
Summary: The crystallization experiment of molten rare earth (RE) slag under different cooling rates was conducted to study the element migration and phase distribution during the RE phase crystallization. Two RE phases were identified, namely (Ca, Ce, La)5(SiO4)6F and (Ca,Ce,La,Mg)3(Ti,Al,Nb)2O7. The Ca and P elements in the (Ca,Ce,La)5(SiO4)6F phase migrated from the inside to the outside during the cooling crystallization process, forming the Ca3(PO4)2 phase at the outer edge of the phase. The (Ca,Ce,La)5(SiO4)6F phase was distributed inside the furnace-cooled slag, while the (Ca,Ce,La,Mg)3(Ti,Al,Nb)2O7 phase was distributed in the surface layer. Based on the phase distribution characteristics, the central hollowing method was proposed for the preliminary enrichment of valuable elements Ti, Nb, and RE in RE slag.
JOURNAL OF RARE EARTHS
(2023)
Article
Chemistry, Multidisciplinary
Lijie Chen, Jiacong Xu, Xiaoqiang Yu, Lei Tian, Ruixiang Wang, Zhifeng Xu
Summary: Rare earth element recovery in molten salt electrolysis is typically between 91% and 93%, with some losses in waste molten salt slag. Limited research has been done on recycling waste rare earth molten salt slag, and a new approach is needed to improve utilization rates.
FRONTIERS IN CHEMISTRY
(2021)
Article
Chemistry, Physical
Shuyao Li, Junhua Jiang, Zheng Ma, Yanqun Chen, Lanwei Li, Jianli Wang, Chao Wang
Summary: Er-doped Bi0.46Sb1.54Te3 bulk materials were successfully synthesized, with Er doping enhancing carrier mobility and concentration to improve electrical transport properties. The introduction of dispersed secondary phase nanoparticles and pores by Er doping also decreased lattice thermal conductivity, leading to a maximum ZT value of 1.21 at 350 K for the Er-x(Bi0.23Sb0.77)(2-x)Te-3 (x = 0.02) sample.
ACS APPLIED ENERGY MATERIALS
(2021)
Article
Engineering, Chemical
Wei Liu, Zhongqing Xiao, Subodh Das, Wencai Zhang
Summary: This study conducted direct acid leaching to recover rare earth elements from an allanite ore, and examined the effects of operational variables on the extraction efficiency. The results showed that under certain conditions, the extraction efficiency of rare earth elements was high.
MINERALS ENGINEERING
(2024)
Article
Engineering, Electrical & Electronic
Shuxin Duan, Fudong Liu, Lin Li, Xiao Liang, Xiaobo Li, Jimei Shi, Enzhu Li
Summary: This study investigated the effects of rare earth oxides on the crystal structure and microwave dielectric properties of ceramic. It was found that improvements in microwave dielectric properties depend mainly on phase compositions and contents. The research achieved temperature-stable microwave dielectric properties for specific ceramic compositions.
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
(2021)
Article
Engineering, Chemical
Lei Tian, Lijie Chen, Ao Gong, Xuangao Wu, Caifang Cao, Zhifeng Xu
Summary: A recovery method based on magnetic separation, sulfuric acid leaching, HF recycling, water leaching, and fluorination precipitation was developed to solve the recovery problem of rare earths (RE), lithium (Li) and fluorine (F) in rare earth molten salt electrolysis slag. By utilizing this method, rare earth sulfate was transformed into qualified fluoride rare earth products, meeting industrial standards.
MINERALS ENGINEERING
(2021)
Article
Environmental Sciences
Xiongwei Jin, Lingkang Chen, Haixia Chen, Lian Zhang, Wenjing Wang, Hong Ji, Shaofu Deng, Lei Jiang
Summary: The types and microstructures of clay minerals in rare earth ores play crucial roles in controlling the release and leaching process of rare earth elements, as revealed by leaching experiments and microscopic analyses in this study.
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
(2021)
Article
Environmental Sciences
Xiaolin Ou, Zhibiao Chen, Xiuling Chen, Xiaofei Li, Jian Wang, Tianjing Ren, Haibin Chen, Liujun Feng, Yikai Wang, Zhiqiang Chen, Meixia Liang, Pengchang Gao
Summary: Mining activities have significant impacts on the distribution and chemical speciation of rare earth elements, posing serious risks to the environment.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Engineering, Chemical
Bin Ji, Qi Li, Rick Honaker, Wencai Zhang
Summary: The leaching recovery of rare earth elements (REEs) from kaolinite samples was significantly increased by pretreatment through calcination, likely due to the liberation of encapsulated REE-bearing minerals and conversion to more soluble forms. This study also found that the REEs were primarily associated with REE-bearing minerals within kaolinite aggregates, with only a small fraction occurring in an ion-adsorption form. The research suggests that the modes of occurrence and association characteristics of REEs with kaolinite are complex.
MINERALS ENGINEERING
(2022)
Article
Chemistry, Applied
Hao Wu, Huashan Yan, Yanzhen Liang, Sen Qiu, Xiaowen Zhou, Dongmei Zhu, Tingsheng Qiu
Summary: This study investigates the transformation mechanism of fluorinated rare earth molten-salt electrolytic slag roasted with sodium carbonate and the regulation mechanism of rare earth leaching under different roasting conditions. The experimental results show that increasing temperature, time, hydrochloric acid concentration, and liquid-solid ratio can effectively promote rare earth recovery, and the optimal conditions have been determined. Under these conditions, rare earths can be biologically transformed at a lower temperature, and the leaching efficiency of rare earths exceeds 98%.
JOURNAL OF RARE EARTHS
(2023)
Article
Engineering, Chemical
Iryna Makarava, Aliaksandr Kasach, Dzmitry Kharytonau, Irina Kurilo, Markku Laatikainen, Eveliina Repo
Summary: This study investigates the development of an effective technology for recovering critical rare-earth elements (REEs) from end-of-life permanent magnets. Chemical and electrochemical leaching of NdCeFeB magnets in sulfuric acid with varying concentrations of oxalic acid were examined. It was found that efficient separation of REEs can be achieved at specific concentrations of oxalic acid, and the leaching rate is substantially higher in electrochemical leaching compared to chemical leaching.
MINERALS ENGINEERING
(2022)
Article
Engineering, Chemical
Yang Li, Feifei Yang, Jing Xiong, Kejia Liu, Wanhai Xiao, Tao Qi, Zhipeng Dong, Yong Wang
Summary: A two-stage hydrochloric acid leaching process was proposed to recover and primarily separate lanthanum (La) and cerium (Ce) in rare earth polishing powder waste (REPPW). The optimal operation conditions resulted in La enriched solution with a relative purity of 91.11% and Ce enriched solution with a relative purity of 92.85%, and their recovery ratios were 59.47% and 85.15% respectively. The precipitation and calcination process yielded La2O3 with purity of 83.67% and CeO2 with purity of 93.38%. The leaching kinetics and mechanism of La and Ce were also studied.
SEPARATION AND PURIFICATION TECHNOLOGY
(2024)
Review
Polymer Science
Xiao-qi Liu, Xin-xin Zhao, Yan Liu, Ting-an Zhang
Summary: Chitosan is an attractive adsorbent, but there are drawbacks that physical and chemical modifications aim to improve. This paper introduces the research background and analyzes the modification, application, and adsorption mechanism of chitosan and its composite materials, reviews the research progress on the adsorption of metal ions, dyes, and anions, and summarizes the main factors affecting their adsorption performance, while also prospecting the development trend of chitosan as adsorbents.
Article
Materials Science, Multidisciplinary
Chu Cheng, Ke-Xing Song, Zi-Wei Song, Ling-Feng Wang, Qian-Qian Xu, Ling-Liang Zhang, Chao Han, Zhi-He Dou, Ting-An Zhang
Summary: This article presents a new method for preparing a cast WCu composite ingot containing micro- and nano-size tungsten particles through aluminothermic reduction. The study found that the aluminothermic reduction reaction occurs within a temperature range of 1223-1233 K, and the addition of CaO can decrease the exothermic intensity and delay the reaction time.
Article
Engineering, Chemical
Xueke Li, Jinru Han, Yan Liu, Zhihe Dou, Ting-an Zhang
Summary: This article summarizes the development and issues of gas desulfurization technology, discusses key theories and optimal parameters in the desulfurization process, and enhances the added value of desulfurization technology through studying the recycling of desulfurization products.
SEPARATION AND PURIFICATION TECHNOLOGY
(2022)
Article
Metallurgy & Metallurgical Engineering
Qin-qin Sui, Zhi-he Dou, Ting-an Zhang, Zhan-ning Yang
Summary: Potassium titanate whiskers were synthesized using high titanium slag and KOH solution. The conversion of potassium titanate whiskers into titanium dioxide was investigated with hydrochloric acid solution. Higher hydrochloric acid concentration resulted in higher titanium dioxide content and removal of impurities. The morphology of the conversion product varied with acid concentration, forming multibranched and flower-like structures at lower concentrations and slender fusiform structures at higher concentrations.
Article
Materials Science, Multidisciplinary
Chu Cheng, Zi-Wei Song, Ke-Xing Song, Ling-Feng Wang, Tao Huang, Yan-Jun Zhou, Hai-Tao Liu, Shao-Lin Li, Chao Han, Zhi-He Dou, Ting-An Zhang
Summary: In this study, a methodology for preparing aluminum bronze composites reinforced with micro-size tungsten particles through aluminothermic reduction was presented. The adiabatic temperature and thermodynamic equilibrium of the Al-CuO-WO3 system were calculated to synthesize the composites. It was found that the synthesis of the composites was feasible, but temperatures higher than 2000 K hindered the reaction.
Article
Materials Science, Multidisciplinary
Kun Wang, Yan Liu, Zhihe Dou, Guozhi Lu, Xiaofei Li, Ting-An Zhang
Summary: A novel method of extracting iron from high-iron red mud and preparing low-carbon cement clinker from tailings was proposed. Thermodynamics of smelting reduction were calculated and the effects of different conditions on iron recovery were investigated systematically. Experimental results showed that under optimal conditions, the iron recovery rate reached 97.6% and the obtained metal met the industrial standard of pig iron for steelmaking.
Article
Metallurgy & Metallurgical Engineering
Qin-qin Sui, Zhi-he Dou, Ting-an Zhang
Summary: A new method of oxygen-rich alkali conversion in KOH solution was proposed for high-efficiency alkali conversion and impurity removal of high titanium slag under the condition of low alkali concentration. The result showed that the conversion rate of titanium was 97.0%, and the removal rates of silicon and aluminum were 90.2% and 76.2%, respectively, under specific conversion conditions.
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
(2022)
Article
Geochemistry & Geophysics
Baojing Zhang, Tingan Zhang, Zhihe Dou
Summary: With the rising costs of iron and copper ores, the mismatch between the significant imports of these ores into China and the increasing accumulation of unused copper slag has become more pronounced. This study demonstrates a low-value method for utilizing copper slag by processing it through reduction and smelting wear-resistant cast iron. The thermodynamic calculations and experimental investigation reveal that copper, zinc, and lead oxides can be readily reduced, while the reduction of sulfides is more challenging. Under optimized conditions, this newly developed process recovers a high percentage of copper, iron, lead, and zinc from the slag, with the resulting copper-containing molten iron suitable for the production of wear-resistant cast iron.
Article
Materials Science, Ceramics
Hao Shi, Zhihe Dou, Yang Meng, Tingan Zhang
Summary: The effects of reactant proportions on the features of B4C powder synthesized by in-situ magnesiothermic SHS method were investigated. It was found that the reactant proportions were the fundamental reasons affecting the phase composition of the products. Mg addition decreased the Mg3B2O6/MgO mass ratio, while C addition increased the C/B mass ratio of the leached products. The lattice parameters of boron carbide crystal changed with the increase of the C/B mass ratio, and when the ratio exceeded 0.3, the lattice parameters became constants while free carbon appeared in the leached products.
CERAMICS INTERNATIONAL
(2022)
Article
Materials Science, Multidisciplinary
Zhang Baojing, Zhang Tingan, Dou Zhihe, Zhang Dongling
Summary: In order to improve the utilization rate of vulcanizing agent and the dilution effect of copper slag, the vortex stirring dilution method was used in this study. Using a water model, suitable stirring speed and insertion depth of the stirring paddle were determined. The copper recovery reached 88.44% after the fire dilution of copper slag under these conditions.
JOURNAL OF WUHAN UNIVERSITY OF TECHNOLOGY-MATERIALS SCIENCE EDITION
(2022)
Article
Energy & Fuels
Jun Hao, Zhi-he Dou, Ting -an Zhang, Kun Wang, Xing-yuan Wan, Song Qi
Summary: This paper proposes a novel method for comprehensive disposal of fly ash to produce ferrosilicon without slag at low temperature and with high efficiency reduction under the action of Fe2O3. The study systematically investigates the promotion of Fe2O3 on the reduction and decomposition of fly ash, as well as the strengthening mechanism of the reduction and decomposition of mullite phase. Thermodynamic analysis and experimental results support the proposed carbothermal reduction process of fly ash and the decomposition mechanism of mullite, and suggest a new idea of preparing ferrosilicon and alumina/calcium aluminate byproducts through electric furnace melting.
Article
Biochemistry & Molecular Biology
Wei Wang, Chongyu Zhang, Jianyong He, Weijun Peng, Yijun Cao, Jiang Liu, Yukun Huang, Guixia Fan
Summary: This study investigated the self-assembly of chitosan-induced montmorillonite nanosheets (MMTNS) to form a layered and porous composite for adsorbing MB dye wastewater. The self-assembly process was driven by hydrogen-bond interaction, resulting in the formation of two-dimensional lamellae. The MMTNS/CS composite showed a high adsorption capacity for MB through various interactions with the dye molecules.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2023)
Article
Metallurgy & Metallurgical Engineering
Rui Zhang, Xiangwei Liao, Shixiong Li, Yi Min, Chengjun Liu, Ting-an Zhang, Zhihe Dou
Summary: To improve the quality and dephosphorization capacity of steel, it is important to understand the microscopic essence of the slags' dephosphorization reaction. The temperature dependence of phosphorus distribution ratio and phosphate capacity is discussed with regards to the structure characterized by Raman and MAS-NMR. Increasing the temperature weakened the formation of Si-O-Ca-O-P linkages, which stabilizes the silicate and phosphate network and affects the phosphorus distribution ratio and phosphate capacity. The dephosphorization reaction proceeds in the reverse direction with the increase of temperature due to the reduction of NBO/T.
IRONMAKING & STEELMAKING
(2023)
Article
Metallurgy & Metallurgical Engineering
Hao Shi, Zhi-He Dou, Yang Meng, Ting-An Zhang
Summary: In this study, the influence of kinetic factors on the adiabatic temperature in the self-propagation synthesis (SHS) reaction was investigated by varying the experimental conditions of Mg powder particle size and sample pressure. The results showed that the different physical states of the raw materials could lead to completely different reaction endpoints, and the reaction could not be initiated when the particle size of Mg powder was larger than 96 μm. Finer magnesium powder and higher sample pressure accelerated the reaction and reduced by-products, but also increased the evaporation and dissipation of the raw material. The results suggested that the size of magnesium powder near 58 μm and the sample pressure of 30 MPa were suitable experimental conditions.
JOURNAL OF CENTRAL SOUTH UNIVERSITY
(2023)
Article
Materials Science, Multidisciplinary
Jisen Yan, Zhihe Dou, Tingan Zhang
Summary: Spherical Ti6Al4V alloy powder was prepared successfully using calciothermic self-propagating rapid reaction method, showing characteristics of high purity, short production cycle, and environmental friendliness.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2023)
Article
Metallurgy & Metallurgical Engineering
Arsyad Maulana Dzulqornain, Ana Belen Cueva-Sola, Kyeong Woo Chung, Jin-Young Lee, Rajesh Kumar Jyothi
Summary: This study presents a hydrometallurgical process for the separation of light rare earth elements (LREEs) using oxidation, precipitation, solvent extraction, and stripping techniques. Selective oxidation with potassium permanganate was employed for the separation of cerium (III). Solvent extraction with Cyanex 572 and cross-current scrubbing were used to achieve the separation of lanthanum (III) from neodymium (III) and praseodymium (III).
Article
Metallurgy & Metallurgical Engineering
Bo Chen, Shenxu Bao, Yimin Zhang
Summary: This study investigated the effects of Al, Fe, P, Si and Na on the precipitation characteristics of vanadium in the ultrasound precipitation system. The concentration upper limits and the negative influence on the precipitation kinetics were determined for each impurity. The findings provide theoretical and technical support for the industrial application of ultrasound precipitation technology.
Article
Metallurgy & Metallurgical Engineering
Chunlin He, Mingwei Qi, Yun Liu, Zunzhang Liu, Yuezhou Wei, Toyohisa Fujita, Guifang Wang, Shaojian Ma, Wenchao Yang, Junyuan Gan
Summary: In this study, D201 x 7 resin and tartaric acid were used as materials and complexing agents for the separation of germanium from sulfuric acid solution. The study successfully achieved the separation of germanium and demonstrated the high selectivity and adsorption performance of the resin.
Article
Metallurgy & Metallurgical Engineering
Xiaobo Zhu, Yue Liu, Chen Ma, Wang Li
Summary: A selective and highly effective method for the extraction and separation of V(IV) and Fe(III) using N235 and P507 as solvent extractants is proposed. The pH, composition, and concentration of the extractant mixture have significant effects on the extraction efficiency and separation factor. The mixing of P507 and N235 generates the P507 monomer, which enhances the extraction efficiency and weakens the stability of vanadium containing extraction complex. Cation exchange process forms the extraction complexes.
Article
Metallurgy & Metallurgical Engineering
B. Behnajady, J. Yousefi Seyf, S. Karimi, M. Moradi, M. Sohrabi
Summary: Deep eutectic solvents (DES) have potential as environmentally-friendly solvents for recovering metals from spent lithium-ion batteries (LIBs). Experimental and molecular dynamics simulation results showed that the chloride ions in DES can form complexes with lithium, manganese, and nickel ions, facilitating their extraction.
Review
Metallurgy & Metallurgical Engineering
Sebastian Kinas, Dorota Jermakowicz-Bartkowiak, Anna Dzimitrowicz, Piotr Cyganowski
Summary: The high demand for platinum-group metals (PGMs) and Re in economical and industrial applications related to environmental protection and energy conversion/storage has led to resource scarcity. Thus, it is crucial to recover and recycle these rare metals. This study critically reviews the recent progress in the effective recovery of PGMs and Re from materials relevant to sustainable technologies, emphasizing practical aspects, environmental impact, and issues related to the unit processes of recovery.
Article
Metallurgy & Metallurgical Engineering
Guopeng Yang, Qinggang Li, Guiqing Zhang, Mingyu Wang, Zuoying Cao, Wenjuan Guan, Jiawei Du, Shengxi Wu
Summary: The study proposes an efficient, clean, and economical process for recovering V2O5 from titanium-white waste through hydrogen peroxide stripping and precipitation of vanadium products by heating. Experimental results show that the use of D2EHPA as a modifier prolongs the duration of maximum stripping efficiency, enabling continuous operation.
Article
Metallurgy & Metallurgical Engineering
Guisu Yu, Shuainan Ni, Yun Gao, Ditang Mo, Zhiyuan Zeng, Xiaoqi Sun
Summary: This research proposes a novel green process for the selective recovery of rare earth elements (RE) from spent NdFeB permanent magnet using hydrophobic deep eutectic solvent (HDES). Through optimization of extraction conditions and stripping method, efficient and clean separation and recovery have been achieved.
Article
Metallurgy & Metallurgical Engineering
Jia Li, Xinsheng Wu, Xiaozhou Zhou, Li Zeng, Shengxi Wu, Mingyu Wang, Wenjuan Guan, Zuoying Cao, Qinggang Li, Guiqing Zhang
Summary: This paper presents a complete hydrometallurgical route for the full-component utilization of deep-sea polymetallic nodules (DPN), achieving high recovery efficiency and near-zero waste production with low energy consumption.
Article
Metallurgy & Metallurgical Engineering
Sanae Elmisaoui, Abderrazak M. Latifi, Lhachmi Khamar
Summary: A first principles model is developed to describe the dissolution mechanism of phosphate ore particles in a solution of phosphoric acid. The model accounts for non-uniform size of ore particles using particle size distributions and quantifies their influence on the model predictions. A global estimability analysis is carried out to determine the estimable parameters from experimental data, and the predictions show good agreement with the experimental data. The computed activation energy indicates that diffusion is the rate limiting step of the dissolution process.
