WASTE MANAGEMENT
·
2021
·
IF 7.145
Huimeng Yang,Bowen Deng,Xiaoyun Jing,Wei Li,Dihua Wang
Regenerating cathode material from spent lithium-ion batteries (LIBs) permits an effective approach to resolve resource shortage and environmental pollution in the increasing battery industry. Directly renovating the spent cathode materials is a promising way, but it is still challenging to efficiently remove all of the complex impurities (such as binder, carbon black, graphite and current collectors) without destroying the material structure in the electrode. Herein, a facile strategy to directly remove these impurities and simultaneously repair the degraded LiCoO 2 by a target healing method is reported. Specifically, by using an optimized molten salt system of LiOH-KOH (molar ratio of 3:7) where LiNO 3 and O 2 both serve as oxidants, the impurities can be completely removed, while the structure, composition and morphology of degraded LiCoO 2 can be successfully repaired to commercial level based on a two-stage heating process (300 °C for 8 h and 500 °C for 16 h, respectively), resulting in a high recovery rate of approximately 100% for cathode material. More importantly, the regenerated LiCoO 2 exhibits a high reversible capacity, good cycling stability and excellent rate capability, which are comparable with commercial LiCoO 2 . This work demonstrates an efficient approach to recycle and reuse advanced energy materials.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
FUEL
·
2021
·
IF 6.609
Hua Tang,Hongyun Hu,Aijun Li,Baojun Yi,Xian Li,Dingding Yao,Hong Yao,Haoran Yuan
Thermo-chemical recycling of waste tire to generate pyrolytic char as alternative carbon black is a promising route for waste disposal and environmental sustainability. However, impurities in waste tire (like Zn, Si, Ca and S) are probably enriched in the pyrolytic char, and removal of those impurities is of great importance for char recycling. To avoid generating large amount of waste acids and polluted gases in the traditional impurities removing process, molten salt (Na 2 CO 3 -NaOH) thermal treatment was creatively proposed in the current work. The influence of operational temperatures (in the range of 350 to 450 °C) was investigated in relation to the efficiency of impurity removal. Results show that the removal efficiency of impurity components was firstly increased but then weakened by increasing treating temperature from 350 to 450 °C, while the highest removal rate was obtained at 400 °C. Generally, the current system could effectively remove more than 80% of ash and 70% of sulfur at 400 °C, with the recovery rate of char between 71% and 83%. Specifically, calcium carbonate/sulfate was removed from the char due to its good solubility in the molten salts. In addition, molten salts showed good activity to convert char contained inorganic sulfides and ·SH radicals into salts-soluble Na 2 S. Similarly, silicon and zinc were tended to be transformed into soluble silicate and zincate, which had higher solubility in the used molten salt. In addition, the agglomerated char particles were separated into smaller and more uniform size during molten salt thermal treatment.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
HYDROMETALLURGY
·
2015
·
IF 1.933
Huixian Lai,Liuqing Huang,Chenghao Lu,Ming Fang,Wenhui Ma,Pengfei Xing,Jintang Li,Xuetao Luo
To explore the potential of acid leaching in purifying metallurgical grade silicon (MG-Si) for solar cell applications, the effect of silicon microstructure on its leaching behavior was systematically investigated in the present work by a combination of alloying refining with acid etching. The microstructure evolution of silicon was revealed before and after acid etching with different lixiviants. Calcium-containing precipitates were found in MG-Si after alloying with calcium. The etching results showed that the leaching behavior of impurity inclusions strongly depended on the composition of the major impurities. HCl + HF mixture was an effective lixiviant for dissolving impurity inclusions in both MG-Si and its alloy with calcium. The impurity removal efficiency of acid leaching of MG-Si was efficiently improved after alloying. Moreover, the kinetics of acid leaching of MG-Si after alloying with calcium was further discussed based on cracking shrinking model.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
·
2022
·
IF 5.479
Xianping Luo,Kunzhong He,Hepeng Zhou,Yongbing Zhang,Fanxing Xie
Lauryl glucoside (LG) was used for the first time as an impurity removal agent in ionic rare earth leaching solution to strengthen the removal of impurity metal ions and avoid the loss of rare earth effectively. Compared with ammonium bicarbonate (NH 4 HCO 3 ), LG can ensure the high efficiency of impurity removal while avoiding ammonia nitrogen pollution. The impurity removal test showed that 91.03 ± 0.1% aluminum ion (Al 3+ ) removal rate, 92.53 ± 0.2% iron ion (Fe 3+ ) removal rate, and 23.27 ± 1.3% rare earth (Re 3+ ) loss rate could be obtained when NH 4 HCO 3 was used to adjust the pH value of leaching solution to 5.4. But the 99.09 ± 1.9% Al 3+ , 93.13 ± 1.3% Fe 3+ removal rates, 5.33 ± 0.9% rare earth loss rate could be obtained by using LG as impurity remover. Infrared spectroscopy and solution chemical calculation showed that NH 4 HCO 3 reacted with impurity metal ions to form Al(OH) 3 precipitate, and a large amount of carbonate rare earth was formed. However, when LG was used as impurity remover, LG reacted with impurity metal ions to form a new Al-O band and no absorption peak related to rare earth ions that was found in the infrared spectrum . Density functional theory (DFT) calculation showed that at pH 5.4, the interaction intensity between LG and Al(OH) 3 was largest, and rare earth ions did not interact with it. As the pH value of the leaching solution gradually exceeds 5.2, the free rare earth ions changed into the form of rare earth hydroxide. It caused the interaction between LG and rare earth elements to increase, resulting in the loss of rare earth. In addition, LG, as a green surfactant derived from renewable plant raw materials, could degrade naturally without causing environmental pollution . Therefore, using LG as an impurity remover can have a good application prospect in strengthening the impurity removal of ionic rare earth leaching solution.
研究领域:
化学工程
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS B-PROCESS METALLURGY AND MATERIALS PROCESSING SCIENCE
·
2024
·Vol. 55
·期 2
·772-781
·
IF 2.4
Tian Qinghua,He Zhiqiang,Xu Zhipeng,Li Dong,Guo Xueyi
High-purity tellurium is a supporting material for contemporary high-tech industries. Zone refining is commonly used as a reliable final purification step to achieve higher purity levels of tellurium. However, the removal of Selenium (Se)—the most troublesome impurity in tellurium often occurring in quite high amounts—stays as the challenge during zone refining, due to its very unfavorable distribution coefficient. In addition, there is an important factor, essential to predict the zone refining efficiency (required number of passes), which is still seldom explored. Therefore, in the present work, the effect of different number of passes on the purification effect of tellurium was investigated by using 4N tellurium as raw material. Firstly, the possibility of removing vaporized Se through introducing an reductive gas flux was studied by testing initial concentrations of Se (13 ppm) and undergoing different process parameters. The experimental results showed that when the number of passes was 3, the impurity removal rate was low and the purification effect was poor; when the number of zone refining reached 9, the removal rate of most impurities in tellurium reached 100 pct, the removal rate of impurity Se reached 80.15 pct, and the total removal rate reached 89.49 pct, and the purity of tellurium ingot was 5N7.
研究领域:
材料科学
·
冶金学
·
半导体技术
✓ 已验证
DOI
高影响因子
CHINESE CHEMICAL LETTERS
·
2023
·
IF 9.1
Yun Wei,Lei Zhou,Wenbin Hu,Liming Yang,Guang Yang,Chaoqiang Wang,Hui Shi,Fei Han,Yufa Feng,Xuan Ding,Penghui Shao,Xubiao Luo
The efficient and environmentally friendly recycling technology of waste residue that including abundant heavy metal produced during the recovery of lithium batteries has become a research hotspot. Herein, a novelty process of acid leaching-selective electrodeposition-deep impurity removal-regeneration was proposed to recovery of the CuS slag, which has been efficient transferred to high purity cathode copper and commercially available ternary precursors. Copper cathode with a purity of 99.67% was prepared under electrochemical reaction conditions at −0.55 V for 2 h. A novel impurity remover-Mn powder, which was used to remove the residual impurities and as a feedstock for the ternary precursor. Finally, NCM523 was regenerated by co-precipitation. The process is superior to the traditional process in economy, energy consumption, CO 2 emissions, product purity and process duration. This study provides a new approach for solid waste recovery and precious metal enrichment.
研究领域:
环境科学
·
材料科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Yaxing Han,Ji Chen,Hailian Li,Yuefeng Deng
Effective recycling of valuable metals from the spent lithium-ion batteries (LIBs) is of great importance from the perspective of resource recycling and environmental conservation. In this work, a comprehensive recovery process of impurities removal and valuable metals co-extraction from simulated leaching solution of spent LIBs with CA12-TBP system was investigated. Firstly, more than 99.7% of Al, Fe and Cu were removed by co-extraction with 30 vol% CA12 (25% saponification degree) and 20 vol% TBP after three-stage extraction. The Ni, Co and Mn lost in the organic phase were decreased to 0.18%, 0.09% and 0.06% by single-stage scrubbing. Then, Fe, Cu and Al loaded in organic phase were completely stripped by 0.5 mol/L H 2 SO 4 and 0.01 mol/L Na 2 SO 3 through a four-stage stripping. After impurities removal, more than 99.9% of Ni, Co and Mn in the raffinate solution were selectively co-extracted with 30 vol% CA12 (60% saponification degree) and 15 vol% TBP after a three-stage extraction, and 7.88% of Li was co-extracted. Then, after a four-stage scrubbing experiment, only 0.52% of Li was lost in the loaded organic phase, which demonstrated that our system possesses the potential of efficient recovery of Ni, Co and Mn from the spent LIBs. Further, Ni, Co and Mn loaded in the organic were completely stripped with 1 mol/L sulfuric acid, and could be directly used for the preparation of the recycled ternary material precursors. Finally, Li in the raffinate solution was recovered by precipitation using Na 2 CO 3 , with the yield and purity of 96.4% and 99.6%. Overall, this recycling process with high impurity removal efficiency and valuable metals recovery efficiency not only simplify the production process, but also greatly reduces production costs, which is helpful for the regeneration and utilization of spent LIBs.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
·
2024
·
IF 6.9
Shaolong Li,Zepeng Lv,Jilin He,Jianxun Song
At present, the processes of recovering indium-gallium-zinc oxide (IGZO) scraps through hydrometallurgy, pyrometallurgy, or molten salt electro-deoxidation are cumbersome, impurities cannot well be effectively removed, and the environmental benefits are inferior. We herein firstly propose a facile electrochemical method for upcycling of IGZO scraps in ammonium salt aqueous solution at ambient temperature. The feasibility of electro-deoxidation of IGZO in aqueous solution has been verified, using IGZO scraps without further crushing as the cathode and anode. The electro-deoxidation behavior of various oxides exhibits differentiation, among which indium oxide is the most easily deoxidized. This difference hinders the formation of a dense alloy layer on the surface of the IGZO substrate, facilitating the transfer of oxygen ions and enabling continuous electro-deoxidation. Impurities such as aluminum and silicon can be significantly removed, with removal rates of 95.8 % and 75.7 %, respectively, which is also attributed to the difference in electrochemical reduction ability between impurity oxides and IGZO, as well as the solid-state existence of cathode products. The process of upcycling IGZO scraps contributes to recovery with straightforward operation and more adaptable implementation environment, which endows it with optimistic application potential.
研究领域:
材料科学
·
环境工程
·
冶金工程
✓ 已验证
DOI
高影响因子
KOREAN JOURNAL OF CHEMICAL ENGINEERING
·
2025
·Vol. 42
·期 3
·621-632
·
IF 3.2
Lou Wen-bo,Liu Dong-yan,Wang Yun,Zhao Da,Sun Zi-cheng,Zou Yi,Wang Sheng-yan,Cheng Quan-guo,Li Jian-zhong,Liu Hong-hui
Nowadays, the recycling of spent lithium-ion batteries is a key concern in the energy field. Among them, for the purification of Li-containing mother liquor, the targeted multi-means coupling impurity removal methods are mostly employed, which however, inevitably lead to a Li loss of 3–5% and high costs. In this study, a multi-stage hydrolysis method, combining the residual P and Al, Mg, Cu, Zn, Ni, Fe, forming hydroxide-phosphate co-precipitation for the synergistic impurity separation, was adopted. Thermodynamic calculations show that Li + and Mg 2+ are insensitive to pH when pH < 10, and Al, Cu, Zn, Ni, Fe behave similarly in nature. The impurities should be precipitated as: Fe 3+ > Al 3+ > Cu 2+ > Ni 2+ > Zn 2+ > Mg 2+ , with phosphate precipitating first, followed by converting into hydroxide as pH rising. Actual results showed that the order was P > Fe & Al & Cu & Ni & Zn > Mg, and the process was divided into three steps, with separation points at pH = 2.37, 8.66, and 11.00, respectively. All the impurity removal efficiencies were close to 100%, the loss of Li was 1.74%. The optimal conditions for Li 2 CO 3 precipitation were determined: an Na 2 CO 3 addition of 1.5 times the theoretical amount, a temperature of 90 °C, a reaction time of 4 h, and a one-time addition of dosing method. Li precipitation efficiency reaches 90.10%, with a 99.95% purity. The results effectively reduced Li losses and provided a practically feasible basis for the industrial purification of Li-containing mother liquor.
研究领域:
能源与环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF RARE EARTHS
·
2025
·
IF 7.2
Yuanxuan Yu,Meng Wang,Qingping Zhang,Zongyu Feng,Yang Xu,Guang Yang,Zhiqing Yang
In the ion-exchange process for separating and purifying rare earth elements, the separation is primarily achieved through the differences in the complexation reactions between the rare earth elements and the eluent. Therefore, enhancing these reaction differences is crucial to improving separation efficiency. In this study, the dissociation constants of ethylene diamine tetraacetic acid (EDTA) at different temperatures were determined by pH potentiometric titration. The speciation evolution of metal-EDTA complexes was elucidated through simulations conducted with Visual MINTEQ, enabling a systematic investigation into the temperature dependence of stability constants for EDTA complexes with La 3+ and representative impurity metal ions (Ce 3+ , Mg 2+ , Al 3+ , Ca 2+ , Cu 2+ , Zn 2+ ). Building upon this, static desorption studies and ion-exchange experiments were conducted to validate the removal of key impurities in lanthanum oxide. Experimental results show that, Mg 2+ and Ca 2+ exhibit better selective separation from La 3+ due to the significant differences in complexation constants. The difference in complexation stabilization constants between La 3+ and impurity ions reaches the maximum at 30 °C. The temperature primarily enhances the reaction difference in the separation system by modulating the distribution of complex species. Desorption studies indicate that increasing the temperature improves the separation coefficient between La and impurity elements. After optimization, the ion-exchange method achieves a La recovery rate of 84.91 wt% and a total impurity removal rate exceeding 92.50 wt%. Under the optimized elution conditions, an elution process was applied to the real feed solution, yielding a lanthanum oxide product with a relative purity of 99.99991 wt%. This work deepens the understanding of temperature-induced regulation of complexation stability constants and provides a novel approach for ion-exchange purification of rare earth elements.
研究领域:
化学工程
·
稀土分离
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION SCIENCE AND TECHNOLOGY
·
2023
·
IF 2.8
Yupeng Liu,Zheng Tong,Mengqian Ni,Xibing Ren,Xiangning Bu,Huaizhi Shao,S. Chehreh Chelgani
As a systematic study, this investigation explored the effects of various leaching conditions (hydrochloric (HCl) acid concentration, solid–liquid ratio, temperature, reaction time, and stirring speed on graphite impurity removal rate) to model the ash removal leaching kinetics and evaluated their mechanisms by analytical analyses. The single-factor results indicated that the optimal impurity removal rate (α) was 14.64% at 8 mol/L HCl concentration, 0.1 g/mL solid–liquid ratio, 343 K acid leaching temperature, 120 min reaction time, and 400 rpm stirring speed. Iron-bearing minerals were efferently removed using HCl. The kinetic process analyses indicated that the aphanitic graphite acid leaching process for the ore fitted well with the unreacted shrinkage core model (diffusion reaction). The reaction’s apparent activation energy (Ea) was 23.43 kJ/mol, and the leaching process’s frequency factor (A) was 15.17. The kinetic equation could be considered as (1 − 3(1−α))2/3+2(1−α) = 15.17e–23.43/(RT)t. From the results, it was concluded that the HCl acid leaching process belongs to diffusion control.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
MINERALS ENGINEERING
·
2025
·
IF 5
Yameng Ma,Jianguo Li,Zhichao Wu,Xiumin Tan,Haiqi Zhang,Xiufeng Zhang,Yuejun Yi
High-purity quartz (HPQ) serves as a critical raw material for strategic high-tech industries. This study focused on the leaching purification of HPQ derived from Xinjiang pegmatitic quartz concentrates. Four leaching reagents (RL, RH, OL, and OH) were systematically evaluated to optimize process parameters including liquid-to-solid ratio (L/S), leaching temperature, and reaction time. Orthogonal experimental design with three factors (L/S ratio, temperature, time) and three levels was employed to determine optimal conditions. The results indicated that OL reagent with an L/S ratio of 2.9:1 at 56.6 °C for 6.8 h achieved the best performance: total impurity content reduced to 16.98 μg/g, impurity removal efficiency reached 92.65 %, and product yield remained at 93 %. The final product met the impurity specifications of SJ/T 11386-2009 (China) for photovoltaic crucible applications, demonstrating its potential as a domestic alternative to imported HPQ. This study provides a novel reagent system and optimized process for HPQ production from pegmatitic sources. Future work should focus on scale-up verification and environmental impact assessment of the proposed process.
研究领域:
矿物学
·
材料科学
·
化工技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）