DESALINATION
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2025
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IF 9.8
Shishuo Wang,Fei Guo,Xuemei Wu,Yuandong Jia,Gaohong He,Xiaobin Jiang
Lithium and its compounds are critical strategic resources with wide-ranging applications. This study developed a bipolar membrane precipitation coupled electrodialysis enrichment (BMp-EDe) process for extracting lithium from brines with an Mg/Li ratio of 20. The method is based on phase separation achieved through precipitation-coupled ion permeation and a synergistic mechanism for ion enrichment, resulting in significant process intensification. Key factors such as current density, molar ratio between diluate and base chambers, and base chamber concentration were optimized to control nucleation and prevent membrane fouling. Under conditions of current density ranging from 200 to 400 A·m −2 and a molar ratio of the diluate chamber to the base chamber between 13 and 16, the magnesium removal rate in the BMp-EDe process is found to exceed 99.90 %, with a separation factor greater than 20,000. The optimal separation factor is observed to reach 40,244, with a magnesium removal rate as 99.96 % and a lithium recovery rate as 95.32 %. With optimized operation conditions, the energy consumption of magnesium precipitation decreased from 11.89 kWh·kg −1 (Mg 2+ ) to 7.97 kWh·kg −1 (Mg 2+ ). Thus, an alternative method is presented that employs commercial bipolar membranes to achieve ultra-high magnesium‑lithium separation efficiency. Additionally, a mechanism for the continuous operation of the magnesium precipitation chamber is validated, which can effectively prevent membrane fouling.
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
JOURNAL OF MEMBRANE SCIENCE
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2023
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IF 9.5
Huawen Peng,Yongjin Hu,Shaoping Li,Jingyi Rao,Qiang Zhao
High performance Mg 2+ /Li + separation membranes are needed to meet the rising demands for lithium supply, yet state-of-the-art polyamide nanofiltration membranes show limited permeance due to relatively dense structures. This work exploited sulfonium salts for the first time to modify nanofiltration membranes , leading to sulfonium-polyamide membranes with high Mg 2+ /Li + separation performance. The occurrence and competition of three types of reactions during the surface modification process were studied and correlated to properties of resultant membranes. Both the positive charge and loose structures of polyamide membranes were enhanced as a result of sulfonium modification, leading to ∼4.3 times improved permeance. The modified membrane exhibited water permeance (∼26.4 L m -2 h -1 bar -1 ) that is one of the top tier values among recent membranes, coupled with good Mg 2+ /Li + selectivity (∼11) in separating high Mg 2+ /Li + ratio feed (∼103). Moreover, the modified membrane showed good stability during one-month continuous operation. This work shows the promising potential of sulfoniums for engineering advanced lithium extraction membranes.
研究领域:
材料科学
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环境工程
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Keting Li,Yufan Hao,Na Yang,Longfei Zhang,Luhong Zhang,Yongli Sun,Bin Jiang
Polyethyleneimine (PEI) nanofiltration (NF) membranes demonstrate remarkable effectiveness in separating lithium and magnesium from salt lakes, attributed to their positively charged surface. However, undesired permeability resulting from densely cross-linked structures limits the further industrial applications and development of PEI NF membranes. Herein, a high permeable Mg 2+ /Li + separation NF membrane with stronger internal and surface positive charge was fabricated using 1-Aminopyridinium iodide (1-AI) for the first time through a capping-grafting synergistic strategy. On the one hand, the monoamine character of 1-AI can realize the end-capping (EC) effect on the acyl chloride monomers in the interfacial polymerization process, which can contribute to a reduction in the cross-linking degree of the membrane. On the other hand, 1-AI with a quaternary ammonium group as the surface grafting (SG) agent can significantly improve the surface positive charge property of the membrane. The synergistic effect of capping-grafting not only rendered the membrane looser and effectively enhanced the surface positive charge of the membrane, but also increased the depth of grafting modification, leading to a notable rise in the internal positive charge of the membrane. After the capping-grafting treatment, the water permeance of the PEI-EC/SG membrane reached 19.8 L·m −2 ·h −1 ·bar −1 , approximately 4.5 times that of the original PEI membrane, while keeping an ideal MgCl 2 rejection rate (97.1%) and exhibiting good Mg 2+ /Li + selectivity (27.7). This work demonstrates the advantages of the capping-grafting synergistic method in regulating membrane structure for improving permeability as well as the surface and internal charge properties of the membrane for enhancing ion selectivity.
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
·
IF 8.4
Yingyao He,Guiliang Li,Haibo Lin,Qiu Han,Yinlu Ye,Jianqiang Wang,Fu Liu
Selective separation property enhancement is quite important for membranes separations, especially for high mass ratio Mg 2+ /Li + separations. Low selectivity and unclear separation mechanism are the challenges for current membranes. In this study, we designed 4-aminophenyl-15-crown-5 incorporated polyamide nanofiltration membranes through interfacial polymerization for Li + enrichment. The electrochemical tests and energy barrier calculations using transition state theory confirmed that the crown ether in nanofiltration membrane is responsible for governing Mg 2+ transportation, resulting in a substantial energy barrier impeding its transport. Furthermore, a two-stage nanofiltration process was employed to enhance Li + enrichment in simulated brine and achieved 35-fold increase in Li + enrichment using as-fabricated membranes. These results demonstrate the substantial potential for Li + extraction from brine with a high Mg 2+ /Li + mass ratio using the crown ether incorporated membrane. Meanwhile, the proposed strategy incorporating transport barriers presents a novel approach for designing ion-selective channels within membranes.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
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IF 8.4
Faizal Soyekwo,Changkun Liu,Xin Mao,Ruixin Nie
Efficient magnesium-lithium separation is key to extracting lithium resources from salt lake brines. However, efficient magnesium-lithium separation is constrained by the high magnesium-to-lithium ratios on the nanofiltration separation performance due to the weakened Donnan effect and inherent permeability-selectivity trade-off behaviour. To address this challenge, a dual methylpiperidinium ionic liquid was designed in this work and incorporated into polyamide networks to manipulate the structural properties of polyamide membrane for improved magnesium/lithium separation. We demonstrate that the piperidinium modification of polyamide networks not only modulated and enhanced the morphology, hydrophilicity , free volume and electropositivity, but also synergized the steric hindrance differentiation inside the membrane nanochannels . These structural advantages enabled the modified membrane to achieve high-separation performance with enhanced water permeance of 37.3 L m −2 h −1 bar −1 and Mg 2+ /Li + selectivity of 30.6 (for Mg/Li mass ratio of 31.2). Molecular dynamics simulations further confirmed that the fast water transport and the difference in the ion separation behaviour are strongly correlated to the enhanced structural properties of membranes. We expect this work to provide insightful guidance for engineering high-performance membranes and make contributions in the application of nanofiltration in lithium mining from high Mg/Li ratio brines.
研究领域:
材料科学
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环境工程
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2025
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IF 9
Yaoxian Hu,Hui Su,Wensen Liu,Zhaowu Zhu,Tao Qi
Effective lithium extraction from magnesium-rich brines is crucial to meet the increasing lithium demand. Traditional solvent extraction using tributyl phosphate (TBP) as the main extractant exhibits limited Li/Mg separation and dissolution losses during long-term operation. Herein, a novel ionic liquid-assisted lithium extraction system (2-Ethylhexyl diphenyl phosphate (DPOP)/1-Ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide [Emim][NTf 2 ]) using organophosphate containing rigid phenyl groups was proposed. The phenyl group increased the steric hindrance of the extractant, enhancing the system efficiency for separating Li + from impurities. Results demonstrated that introducing the phenyl group into phosphate considerably improved the Li/Mg and Li/Ca separation factors, reaching 4,641 and 93, respectively, under optimal conditions, with a single-stage Li + extraction efficiency of 67%. After washing and stripping, a LiCl solution (purity = 99.68%) was obtained. Electrospray ionization mass spectrometry confirmed that the molecular formula of the extracted Li + complex was [Li·2DPOP][NTf 2 ]. Subsequent density functional theory calculations on the complexes revealed shorter bond lengths for the DPOP/[Emim][NTf 2 ] system with Li + than those with Mg 2+ and more negative binding energy and Gibbs free energy change during Li + extraction. Therefore, this system preferentially extracts Li + with tighter and more stable binding than Mg 2+ , exhibiting excellent Li selectivity.
研究领域:
化学工程
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材料科学
✓ 已验证
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
Guoke Zhao,Ying Wan,Guoyuan Pan,Hao Yu,Gongqing Tang,Xiaozhi Gong,Yang Zhang,Jie Sun,Yiqun Liu
Lithium extraction from brine sources such as salt lakes, seawater, and produced water from oil/gas fields is garnering increasing interests from the academic and industrial sectors due to its cost-effectiveness and reduced environmental impact. A critical technological challenge is the efficient separation of Mg 2+ and Li + ions. Many researchers have reported the preparation of positively charged nanofiltration membranes with quaternary ammonium groups, yet investigations about quaternary phosphonium groups are scarce. In this work, positively charged nanofiltration membranes were prepared utilizing polyethyleneimine as the aqueous phase monomer, trimesoyl chloride as the organic phase monomer, and 3-bromopropyl triphenyl phosphonium bromide as the functionalizing monomer. The TFC-P + membranes, enriched with a high density of quaternary phosphonium groups and an enhanced Donnan effect, achieve a MgCl 2 rejection of 98.9 %, a Mg 2+ /Li + selectivity of 81.6, and a water flux of 50 LMH under 0.5 MPa. The membranes possess an enhanced comprehensive separation capability that exceeds that of the majority of nanofiltration membranes documented in scholarly articles. Additionally, the membranes exhibit outstanding anti-fouling and anti-bacterial characteristics, essential for their industrial applications. The preparation method proposed herein is simple and conducive to continuous production processes. In light of the abundant produced water reserves from oil and gas extraction, future work will focus on pilot-scale lithium extraction experiments.
研究领域:
化学工程
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Water Process Engineering
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2023
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IF 7
Lei Ma,Qiuyan Bi,Wanji Zhou,Xingliang Liu,Fuju Qi,Hao Zhang,Yifan Gao,Shiai Xu
Nanofiltration (NF) membrane with high selectivity and permeance is important for recovering lithium from salt lake brine. In this work, sandwich-like NF membranes were prepared using polyamide (PA) as the interfacial polymerization (IP) layer, dopamine (DA) and zwitterion-g-C 3 N 4 as the composite interlayer and polyethersulfone (PES) ultrafiltration (UF) membrane as the substrate. Three NF membranes were prepared with different zwitterion-g-C 3 N 4 : M3 membrane modified with C 5 H 12 ClNO 2 -g-C 3 N 4 , M4 membrane modified with C 12 H 24 N 2 O 4 S-g-C 3 N 4 and M5 membrane modified with C 19 H 39 NO 2 -g-C 3 N 4 , and their physical and chemical properties, separation capacity, and antifouling behaviour were analyzed. The zwitterion-g-C 3 N 4 composite interlayer improves the hydrophilicity and pore structure of NF membranes. The water contact angle (CA) of M5 membrane is 25.5°and its pore size is 0.49 nm. M5 membrane shows a high retention rate of 96.66 % for Mg 2+ in mixed salt solution (Mg 2+ /Li + = 84) and performs well in salt lake brine with a rejection of 97.90 % to Mg 2+ . The flux recovery ratio (FRR) can be kept above 93 %. This study may give ideas for the preparation of composite NF membrane for water softening and lithium utilization.
研究领域:
材料科学
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环境科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2023
·
IF 9.5
Yifan Zhang,Yaru Fan,Guoli Zhou,Yijun Cao,Jingtao Wang,Xiaobin Jiang,Ning Zhang,Shaohua Yin
With the rapid development of Li-ion batteries (LiBs), the demand for lithium sharply increased. Salt lakes contribute to major extractable lithium in the world, however, the efficient separation of Mg 2+ and Li + remains a challenge. The PEI-based nanofiltration (NF) membrane shows great potential for Mg 2+ /Li + separation in recent studies, due to its positively charged surface and tunable pore size. In this work, ethylenediamine-terminated polyethyleneimine (EDA@PEI) was utilized as the aqueous monomer reacting with trimesoyl chloride (TMC) via interfacial polymerization (IP) to fabricate a new class of PEI-based NF membranes. This work explored critical membrane fabrication parameters and characterizations of EDA@PEI NF membranes. Additionally, this work compared EDA@PEI-TMC and PEI-TMC membranes on their physicochemical properties and NF performance. The results show that PEI containing EDA groups at ends provides the probability for connection of the backbone via TMC, thus enhancing the cross-linking degree (DNC) of EDA@PEI NF membranes. Meanwhile, the presence of EDA groups enhances the Zeta potential of membranes. The best-performing EDA@PEI-TMC membrane exhibits the highest rejection for Mg 2+ of 99.21 %, and excellent Mg 2+ /Li + separation that S Li/Mg reaches 69.20, 80.62 and 46.79 at Mg 2+ /Li + mass ratios of 40:1, 60:1, and 120:1, respectively. During a 48-h NF test, EDA@PEI-TFC membrane shows consistent performance and steady flux. This work demonstrates the great application potential of EDA@PEI NF membranes for Mg 2+ /Li + separation, and provides a candidate for fabricating PEI-based NF membranes.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
·
2025
·
IF 9.8
Jiyue Wang,Yang Xu,Qi Zhang,Qiang Zhao,Zhitian Liu
Surface modification is an effective strategy to improve separation performance of Mg 2+ /Li + nanofiltration membranes, but less is known about how chemical structures of modification molecules affect separation performances of resultant membranes. In this work, three types of quaternary ammonium salts with modulated structures were designed to modify polyethyleneimine-trimesoyl chloride (PEI-TMC) membranes. The surface and cross-section morphologies, mean pore sizes, charge and hydrophilicity properties of the modified membranes were characterized. These quaternary ammonium salts can tune membrane properties effectively, and impart good separation performance to modified membranes. Molecular structures of quaternary ammonium salts affect the diffusion of the monomer into the organic phase and the reactivity with the acyl chloride. The flux of modified membranes are 99.6 Lm −2 h −1 , 112.2 Lm −2 h −1 , and 128.8 Lm −2 h −1 , and the rejection of MgCl 2 are 93.2 %, 94.9 %, and 92.8 %, respectively. The modified membranes also show good retention for heavy metal ions (e.g., Cu 2+ , Cr 3+ , Zn 2+ , Co 2+ , and Ni 2+ ).
研究领域:
材料科学
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化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
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2024
·
IF 8.4
Jingjun Wang,Hao Zhang,Rukang Tian,Huiyan Shen,Wei-Hua Li,Yunkun Wang
The increasing demand for lithium resources in the rapidly growing new energy industry has spurred interest in efficient lithium extraction from salt-lakes using Nanofiltration membranes, owing to their impressive ionic rejection capabilities. However, achieving effective Mg 2+ /Li + selective separation remains a critical challenge for the widespread application of NF membranes in lithium extraction. This study focuses on the utilization of poly(dimethyldiallylammonium chloride)-modified polyethersulfone substrate for interfacial polymerization modulation in the preparation of polyamide nanofiltration membrane. The prepared membrane exhibited high MgCl 2 rejection. And then the prepared membrane was subsequently optimized by post-modification with piperazine. Previous and subsequent modifications resulted in smaller pores, narrower pore size distribution, and lower surface negativity of the modified membrane. These properties contributed to the significantly higher MgCl 2 rejection rate of the modified membrane (94.7%) than that of the Control membrane (46.1%). This excellent rejection property ensured the efficient Mg 2+ /Li + separation performance of the modified membrane. It was noteworthy that the Mg 2+ /Li + separation factor for lithium extraction in simulated brine reached an impressive 77.2. In addition, the modified membrane retained a comparable pure water permeance and Na 2 SO 4 rejection rate as the control membrane and showed excellent stability, significantly improving the Mg 2+ /Li + separation efficiency while reducing energy consumption. This study presents a simple strategy to fabricate NF membranes with excellent Mg 2+ /Li + separation factor.
研究领域:
材料科学
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环境工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Y. Li,Y.J. Zhao,M. Wang,H.Y. Wang
Nanofiltration (NF) is a promising method in lithium extraction from salt lake brine with a high Mg 2+ /Li + mass ratio. However, membrane fouling challenges its applicability and productivity. This study incorporated graphene oxide (GO) into the polyamide (PA) selective layer of NF membranes to enhance anti-fouling properties and improve lithium extraction from brine. Membrane structure analyses revealed that 0.002 wt% and 0.01 wt% GO facilitated the interfacial polymerization reaction. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) results indicated that the PA selective layers in the GO-0.002 % and GO-0.01 % membranes were denser, smoother, and thinner. In contrast, the addition of 0.05 wt% GO resulted in the Turing structures on the membrane surface. Adsorption kinetics indicated pollutant adhesion in the following order: GO-0.05 % > GO-0 % > GO-0.002 % > GO-0.01 %, which was attributed to calcium-carboxyl complexation, as directly measured by AFM and consistent with carboxyl density. The GO-0.002 % and GO-0.01 % NF membranes demonstrated excellent anti-fouling properties in brines, with lower initial fouling rates and higher flux recovery after cleaning, underscoring the significant role of calcium-carboxyl complexation in membrane fouling. The retention of Mg 2+ increased to 95 %, while that of Li + decreased to below −28 % for GO-0.002 % and GO-0.01 % membranes, indicating promising potential for Mg and Li separation. This study provides valuable insights into developing NF membranes with high Mg/Li selectivity and anti-fouling capabilities for lithium extraction from salt lake brine.
研究领域:
材料科学
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环境工程
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化学工程
✓ 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）