WASTE MANAGEMENT
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2025
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IF 7.1
Yuxue Zhang,Zhaoyong Liu,Jiahui Wang,Hui Du,Qi Sun,Ruitong Gao,Zhenming Xu
Recycling Li from spent lithium ion batteries (SLIBs) in an efficient and highly selective manner could protect the environment and introduce the circular economy principle to society. Simultaneously, the urgent need to address plastic waste, particularly polyvinyl chloride (PVC), has become a global concern. In this work, a strategy for Li extraction through synergetic pyrolysis of LiMn 2 O 4 cathode materials (LMO) and PVC is proposed. Under optimal conditions, the recovery rates of lithium and manganese reached 99.89 % and 0.02 %, respectively, demonstrating efficient separation of these elements. Temperature was found to play a critical role in the leaching rates of lithium and manganese by promoting the decomposition and reduction of LMO. Additionally, kinetic analysis shows that the activation energy ( E a ) of the synergetic pyrolysis is 139.60 KJ/mol, and the pyrolysis mechanism satisfies third-order reaction process. Eventually, the proposed mechanism involves the synergistic effects of chlorination and reduction reactions. First, HCl is generated by PVC pyrolysis under the catalytic effect of LMO. Then, the chlorination of HCl with LMO occurs by capturing structural oxygen and generating LiCl and MnCl 2 . Simultaneously, the reduction reaction between the reducing species generated by PVC pyrolysis and LMO occurs to form Li 2 O and MnO, ultimately enabling the separation of lithium and manganese. Overall, this paper presents a novel approach for future applications by providing a theoretical basis for selective Li extraction.
研究领域:
环境科学
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材料科学
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产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Xintong Li,Xiaoya Li,Xin Ma,Zhanfang Cao,Hong Zhong,Shuai Wang
Manganese is a critical metal with widespread applications. The increasing demand for manganese, driven by the rapid growth of the electric vehicle and new energy sectors, has underscored the need for efficient separation and purification technologies, particularly from low-grade ores with high content of impurities. This study applies machine learning (ML) −driven quantitative structure–activity relationship (QSAR) modeling to investigate the Mn 2+ and Mg 2+ separation performance of 14 extractants. Key molecular descriptors were identified through principal component analysis and clustering heatmap method, and QSAR models were developed using ordinary least squares, nonlinear model, artificial neural network, random forest, and extreme gradient boosting (XGBoost) tree. The XGBoost model exhibited superior predictive accuracy for Mn 2+ and Mg 2+ extraction efficiencies and Mn 2+ /Mg 2+ separation selectivity. Feature importance analysis revealed that molecular properties related to hydrophilicity, electronic characteristics, and steric hindrance, as reflected by descriptors such as Clog P, OAV, Nonpolar S, VIP, Max P, and EI, play decisive roles in governing extraction efficiency and separation performance. Further NCI analysis demonstrated that the C–OH group of one α -hydroxyalkyl phosphinic acid ( α -HA) molecule forms a hydrogen bond with the C–OH group of another α -HA molecule, which likely accounts for the tendency of α -HA molecules to form dimers during solvent extraction. This interaction modulates the spatial arrangement of P–OH and P=O groups, enhancing both Mn 2+ extraction efficiency and Mn 2+ /Mg 2+ separation selectivity. These findings underscore the value of ML-driven QSAR modeling in predicting extractant performance, offering new mechanistic insights into Mn 2+ /Mg 2+ separation, and informing the development of novel extractants.
研究领域:
化学工程
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材料科学
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环境科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2024
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IF 8.1
Xiaopeng Jin,Manxing Huo,Qifeng Wei,Xiulian Ren
The separation of aluminum and manganese from mineral leach solutions has been a challenge at present and has attracted great interest. In this paper, the effects of different extractants on aluminum recovery as well as the effects of the concentration of the most suitable extractant, extraction temperature, initial pH and organic phase/aqueous phase ratio on the recovery of aluminum were investigated. The results showed that for chromite recovery solution(CRS) with an initial aluminum concentration of 0.1221 g/L, S-NA at 0.25 mol/L exhibited good selectivity and extraction efficiency for aluminum, and was able to separate aluminum from other elements and recover it easily for secondary use without scrubbing. The extraction mechanism of aluminum in sulfuric acid medium was investigated through various analyses including the combination of energy and bond length calculations, electrostatic potential (ESP) theory calculations, IGMH analysis, process chemistry analysis, and thermodynamic equilibrium species calculations. These analyses showed that Al(III) was distributed in the recycling solution in the form of AlSO 4 + and had strong interactions with naphthenate ions, and that the combination of AlSO 4 + with the naphthenate ions(R − )’s formed the stable complex molecule AlSO 4 R. The study provides a feasible path for the recovery of aluminum in CRS and is of guiding significance for the theoretical study of aluminum in sulfuric acid media.
研究领域:
化学工程
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材料科学
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产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Ao Zhou,Zhihong Liu,Zhiyong Liu
With the imminent peak in the retirement of rechargeable lithium-ion batteries worldwide, the development of efficient methods for recycling valuable elements from LIBs has attracted considerable attention. In this work, a novel method of NH 4 HSO 4 reduction roasting-selective ammonia leaching was proposed to thoroughly separate Li and Mn from the spent LiMn 2 O 4 cathode materials . Using the TG-DSC-FTIR, XRD, SEM-EDS and ICP methods, the detailed mechanism of reduction roasting process was revealed, showing that the Mn 4+ and Mn 3+ in the spinel structure of LiMn 2 O 4 were reduced by the NH 4 + from the molten ammonium salt, and transformed into water-soluble MnSO 4 and Li 2 Mn 2 (SO 4 ) 3 . According to the water-leaching performance of the roasting products, the sulfation conversion rate of Mn reaches 98.1 %, while Li is almost completely transformed under the optimal roasting conditions (475 ℃, 60 min). Using the NH 3 ·H 2 O-air leaching-system, complete separation of Li and Mn can be achieved. It was shown that the introduction of air into the ammonia solution at a rate of 0.2 L/min under the optimal leaching condition leads to Mn precipitation in the form of nanoscale Mn 3 O 4 particles with a precipitation rate of over 99.99 %, while Li still remains completely leached. Based on the in situ detection of the oxidation reduction potential and pH during the selective leaching, the key mechanism of efficient Mn precipitation was revealed. that is, the increasing potential accelerates the oxidation of Mn(OH) 2 , and the rapid consumption of Mn(OH) 2 promotes the hydrolysis of Mn 2+ , thereby achieving a significant improvement in the separation efficiency of Li and Mn.
研究领域:
材料科学
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环境工程
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化学工程
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产品关联
DOI
高影响因子
CHEMOSPHERE
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2024
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IF 8.1
Yanfang Huang,Meimei Wang,Bingbing Liu,Shengpeng Su,Hu Sun,Shuzhen Yang,Guihong Han
Ion precipitation flotation technology was demonstrated to be an efficient method for the separation of valuable metals from low-concentration solution. However, the selective separation of three metals from mixing solution is a great challenge, and highly selective reagents are the key to polymetallic separation. In this work, stepwise separation of Co and Zn from the simulated zinc hydrometallurgy wastewater containing ternary Co–Zn–Mn metals by ion precipitation flotation process was proposed. It's demonstrated that organic reagents of 1-nitroso-2-naphthol (NN) and sodium dimethyldithiocarbamate (SDDC) had excellent selectivity for the capture of Co and Zn to form respective precipitate from wastewaters via the chelation reactions. After precipitation, dodecylpyridinium chloride (DPC) and tetradecyltrimethylammonium bromide (TTAB) were chosen as surfactants for the separation of Co and Zn sediments from the solution via the flotation process. The effects of solution pH, molar ratio, reaction temperature, and reaction time on the selective precipitation efficiencies of Co and Zn as well as the effects of surfactant dosage and flotation gas velocity on the flotation separation efficiencies were systematically investigated. It's demonstrated that the comprehensive recovery rates of Co, Mn, and Zn reach 98%, 90%, and 99%, respectively. After separation, oxidation calcination of the foam products was conducted to prepare high-purity Co 3 O 4 and ZnO nanoparticles in which the organic matters were burnt out with gas emissions. The stepwise chelation capture mechanisms of Co and Zn by highly selective precipitation reagents were minutely discussed. It's demonstrated that the proposed selective stepwise precipitation and flotation method is suitable for recovery of critical metal ions from low-concentration polymetallic wastewaters.
研究领域:
环境科学
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冶金工程
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化学工程
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）