Journal of Membrane Science最新文献

Methanol tolerable ultrathin proton exchange membrane fabricated via in-situ ionic self-crosslinking strategy for high-performance DMFCs 通过原位离子自交联策略为高性能 DMFC 制作耐甲醇的超薄质子交换膜

IF 8.4 1区工程技术 Q1 ENGINEERING, CHEMICAL

Journal of Membrane Science

Pub Date : 2024-11-14 DOI: 10.1016/j.memsci.2024.123510

Yixin Luo , Jie Wang , Fuqiang Hu , Ting Qu , Hai Liu , Zushun Xu , Chunli Gong , Guoliang Liu , Ying Ou

Proton exchange membranes (PEMs) with high proton conductivity, mechanical stability, and methanol barrier capability is urgently needed for direct methanol fuel cell (DMFCs). In response, a series of highly sulfonated polybenzimidazoles (SPBI) were synthesized, followed by the creation of a unique in-situ ionic self-crosslinking mechanism via acid-base pair interactions between –SO₃^- and protonated N within the imidazolium rings of SPBI in an acidic milieu. The in-situ ionic self-crosslinking not only significantly enhances the mechanical stability of the prepared membrane, but also constructs a microstructure with a free volume radius smaller than the molecular dimensions of methanol, subsequently imparting unparalleled resistance to methanol permeation. After being reduced to an ultrathin thickness of 15 μm, the optimal SPBI-SO₃H-200 % membrane obtains remarkable high specific proton conductivity of 33.48 S cm⁻². Furthermore, the assembled DMFC demonstrates an exceptionally low methanol crossover current density of 188.25 mA/cm² alongside high power density of 109.92 mW cm⁻² within 2 M methanol fuel, significantly outperforming the methanol crossover current density of 386.06 mA/cm² and power density of 87.13 mW cm⁻² achieved by a single cell assembled with Nafion 115 membrane.

直接甲醇燃料电池（DMFC）迫切需要具有高质子传导性、机械稳定性和甲醇阻隔能力的质子交换膜（PEM）。为此，我们合成了一系列高度磺化的聚苯并咪唑（SPBI），然后在酸性环境中通过 SPBI 中咪唑环上的 -SO3- 和质子化 N 之间的酸碱对相互作用建立了独特的原位离子自交联机制。原位离子自交联不仅显著提高了制备膜的机械稳定性，还构建了自由体积半径小于甲醇分子尺寸的微观结构，从而赋予膜无与伦比的抗甲醇渗透能力。最佳的 SPBI-SO3H-200 % 膜在减薄至 15 μm 的超薄厚度后，获得了 33.48 S cm-2 的超高比质子电导率。此外，组装好的 DMFC 在 2 M 甲醇燃料中显示出 188.25 mA/cm2 的超低甲醇交叉电流密度和 109.92 mW cm-2 的高功率密度，大大超过了用 Nafion 115 膜组装的单电池所达到的 386.06 mA/cm2 的甲醇交叉电流密度和 87.13 mW cm-2 的功率密度。

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引用次数: 0

Stringing covalent organic framework particles for preparing highly loaded mixed-matrix membranes for efficient and precise dye separation 串联共价有机框架颗粒，制备高负载混合基质膜，实现高效精确的染料分离

IF 8.4 1区工程技术 Q1 ENGINEERING, CHEMICAL

Journal of Membrane Science

Pub Date : 2024-11-14 DOI: 10.1016/j.memsci.2024.123509

Cai Zhang, Yinyu Li, Rongxin Huang, Xiaogeng Lin, Yang Huang, Yasan He

Covalent organic frameworks (COFs) based mixed-matrix membranes (MMMs) combining the merits of processable polymers and ordered porosity are potential for molecular separation. However, it remains a challenge to control the interfacial compatibility to prepare high COFs loaded MMMs. Herein, we developed a facile strategy of “Stringing COF particles” for improving the interfacial compatibility to prepare high COFs loaded MMMs with high separation performance. The MMMs could be prepared by simply mixing COF powders with chitosan (CS) solutions, without needing the complicated nanosheetization or modification of COFs. Three typical COFs were synthesized and tested. The suitable large pore size and good hydrophilicity of COFs were confirmed crucial to the “Stringing” strategy. Characterizations indicated CS could enter the larger pores of the COFs (named COF-TADH) and firmly string COF particles together via strong H-bonding to obtain a tightly assembled COF-TADH@CS layer with COFs loading up to 67 wt%. The fabricated 67%COF-TADH@CS/nylon membrane exhibited excellent permeance and stable 100 % rejection to Coomassie brilliant blue (BB), highly competitive compared with other reported membranes. The high COFs loaded MMMs maintain the sieving merits of ordered COF pores, achieving precise separation of the mixed BB/Methyl orange (MO) solution with only MO penetrating through.

基于共价有机框架（COFs）的混合基质膜（MMMs）结合了可加工聚合物和有序多孔性的优点，具有分子分离的潜力。然而，如何控制界面相容性以制备高 COFs 负载的混合基质膜仍是一项挑战。在此，我们开发了一种 "串联 COF 颗粒 "的简便策略，用于改善界面相容性，制备具有高分离性能的高 COFs 负载 MMM。只需将 COF 粉末与壳聚糖（CS）溶液混合即可制备 MMM，而无需对 COF 进行复杂的纳米片化或改性。我们合成并测试了三种典型的 COF。经证实，COF 具有合适的大孔径和良好的亲水性，这对 "串联 "策略至关重要。表征结果表明，CS 可以进入 COF 的较大孔隙（命名为 COF-TADH），并通过强 H 键将 COF 颗粒牢固地串联在一起，从而获得紧密组装的 COF-TADH@CS 层，COF 含量高达 67 wt%。所制备的 67%COF-TADH@CS/ 尼龙膜具有出色的渗透性，对库马西亮蓝（BB）的抑制率稳定在 100%，与其他报道的膜相比具有很强的竞争力。高COFs负载的MMMs保持了有序COF孔的筛分优点，实现了BB/甲基橙（MO）混合溶液的精确分离，只有MO可以透过。

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引用次数: 0

High rejection seawater reverse osmosis TFC membranes with a polyamide-polysulfonamide interpenetrated functional layer 具有聚酰胺-聚磺酰胺互穿功能层的高排斥海水反渗透 TFC 膜

IF 8.4 1区工程技术 Q1 ENGINEERING, CHEMICAL

Journal of Membrane Science

Pub Date : 2024-11-14 DOI: 10.1016/j.memsci.2024.123507

Qihang Li , Liyi An , Chuning Shang , Jianqiang Meng

Current polyamide thin-film composite (TFC) membranes for seawater reverse osmosis (SWRO) require enhanced rejection capabilities for high salinity application and the removal of neutral micropollutants. In this study, we developed high rejection SWRO membranes utilizing m-phenylenediamine (MPD) as the water phase monomer, trimethyl chloride (TMC) as the organic phase monomer, and naphthalene-1,3,6-trisulfonyl chloride (NTSC) as a molecular plug. Xylene was added to the heated organic phase to compensate for the flux loss due to the tightened functional layer. The membranes were characterized in detail with ATR-FTIR, XPS, SEM, AFM, WCA, surface zeta potential, Positron annihilation spectroscopy (PALS), and quartz crystal microbalance (QCM). Our results indicate that adding xylene into the organic phase enhances flux, while heating the organic phase to 90^oC benefits both flux and rejection. Furthermore, the addition of NTSC further improves the rejection. The variation in membrane flux correlates with the functional layer morphology under SEM and the membrane rejection properties correspond well with the functional layer free volume results by PALS. Due to the low reactivity of sulfonyl chloride, NTSC can only form oligomers embedding into the polyamide network, resulting in significantly higher rejection of sodium chloride (99.90 %) and boron (92.39 %) with a flux of 37.85 L m⁻² h⁻¹ under the conditions of 35000 ppm NaCl and 5 ppm boric acid at 800 psi. This work demonstrates that high rejection SWRO membranes can be successfully achieved by an in situ “swelling and filling” method.

目前用于海水反渗透（SWRO）的聚酰胺薄膜复合（TFC）膜需要增强高盐度应用和去除中性微污染物的排斥能力。在这项研究中，我们利用间苯二胺（MPD）作为水相单体，三甲基氯化物（TMC）作为有机相单体，萘-1,3,6-三磺酰氯（NTSC）作为分子栓，开发出了高排斥率的 SWRO 膜。在加热的有机相中加入二甲苯，以补偿由于功能层收紧而造成的流量损失。利用 ATR-FTIR、XPS、SEM、AFM、WCA、表面 zeta 电位、正电子湮灭光谱 (PALS) 和石英晶体微天平 (QCM) 对膜进行了详细表征。我们的研究结果表明，在有机相中加入二甲苯可提高通量，而将有机相加热到 90 摄氏度则有利于通量和排斥。此外，添加 NTSC 还能进一步提高排斥效果。膜通量的变化与 SEM 扫描仪下的功能层形态相关，而膜的排斥特性与 PALS 功能层自由体积的结果非常吻合。由于磺酰氯的反应活性较低，NTSC 只能形成低聚物嵌入聚酰胺网络，因此在 35000 ppm NaCl 和 5 ppm 硼酸、800 psi 的条件下，氯化钠（99.90%）和硼（92.39%）的截留率显著提高，通量达到 37.85 L m-2 h-1。这项工作表明，通过原位 "膨胀和填充 "方法，可以成功实现高排斥率的 SWRO 膜。

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引用次数: 0

Lattice-defective metal-organic framework membranes from filling mesoporous colloidal networks for monovalent ion separation 用于单价离子分离的填充介孔胶体网络晶格缺陷金属有机框架膜

IF 8.4 1区工程技术 Q1 ENGINEERING, CHEMICAL

Journal of Membrane Science

Pub Date : 2024-11-14 DOI: 10.1016/j.memsci.2024.123508

Yihao Xiao, Yanqing Yu, Xinxi Huang, Kun Niu, Wanbin Li

Ionic separations are critical to various chemical, environmental, and energy-related industries, but precise discrimination of monovalent ions with similar properties is extremely difficult. Nanoporous metal-organic framework (MOF) membranes attract intensive attention for ionic separations. However, precise adjusting transport nanochannels of frameworks and simplifying formation mechanisms of membranes remain extremely challenging. In this study, we report controllable construction of lattice-defective MOF membranes for sharp ion sieving, through filling mesoporous MOF colloidal layers by confined interior growth. By utilizing highly processable mesoporous colloidal networks to provide abundant nucleation sites, decelerate precursor diffusions, and serve as membrane-forming hosts, interior MOF growth can be confined in the mesopores of hosts, thereby eliminating any avoid spaces and constructing pinhole-free membranes in a scalable route. Moreover, through creating linker-missing lattice defects in frameworks, the microporous pathways can be accurately expanded at angstrom level, consequently, selectively improving the accessibilities for specific monovalent cations but maintaining the large resistances for others. Importantly, the prepared 150-nm MOF membranes exhibit good long-term stability and superb ion-sieving performance, especially for monovalent cations, with mixture selectivities as high as 7.5 for K⁺/Li⁺ and 51 for K⁺/Mg²⁺ during concentration-driven separations, which outperform most membranes. This study provides an alternative methodology to construct high-performance ion-sieving polycrystalline membranes.

离子分离对各种化学、环境和能源相关行业至关重要，但要精确区分性质相似的单价离子却极为困难。纳米多孔金属有机框架（MOF）膜在离子分离方面受到广泛关注。然而，精确调整框架的传输纳米通道和简化膜的形成机制仍然极具挑战性。在本研究中，我们报告了通过限制内部生长填充介孔 MOF 胶体层，从而可控地构建晶格缺陷 MOF 膜，以实现尖锐的离子筛分。通过利用高度可加工的介孔胶体网络提供丰富的成核位点、减慢前体扩散并作为成膜宿主，MOF 的内部生长可以被限制在宿主的介孔中，从而消除任何避免的空间，并以可扩展的方式构建无针孔膜。此外，通过在框架中制造链接器缺失的晶格缺陷，可以在埃级水平上精确地扩展微孔通路，从而选择性地改善特定一价阳离子的通路，但对其他阳离子则保持较大的阻力。重要的是，制备的 150 纳米 MOF 膜具有良好的长期稳定性和优异的离子筛分性能，尤其是对一价阳离子，在浓度驱动分离过程中，K+/Li+ 和 K+/Mg2+ 的混合选择性分别高达 7.5 和 51，优于大多数膜。这项研究为构建高性能离子筛分多晶膜提供了另一种方法。

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引用次数: 0

Ultrathin cyclodextrin-based nanofiltration membrane with tunable microporosity for antibiotic desalination 用于抗生素脱盐的具有可调微孔的超薄环糊精基纳滤膜

IF 8.4 1区工程技术 Q1 ENGINEERING, CHEMICAL

Journal of Membrane Science

Pub Date : 2024-11-13 DOI: 10.1016/j.memsci.2024.123504

Linlong Zhou , Shuyun Gu , Fang Xu , Jin Zhang , Zheyi Hu , Siyao Li , Zhi Xu

Nanofiltration (NF) membranes play a crucial role in ion separation and antibiotic purification due to their energy efficiency and environment-friendliness. However, conventional polymeric membranes are susceptible to the “trade-off” between permeability and selectivity due to the lack of intrinsically rigid micropores. Herein, the amino-cyclodextrins (amino-CDs) with different cavity sizes were synthesized and employed as the building block to construct 15-nm-thick nanofilms. The rational incorporation of macrocycles with well-defined and tunable cavity into nanofilm enabled a significant enhancement of water permeance and a precise manipulation of molecular weight cut-off of the membranes. Thanks to the significant difference of inherent energy barrier for passage of ions through CD cavity, the CD-incorporated membranes achieved a high Cl⁻/SO₄²⁻ selectivity of 87. In addition, the CD-regulated membranes showed an excellent antibiotic desalination performance, out-performing the state-of-the-art membranes for antibiotic purification. This work provides a gateway to the development of nanofiltration membranes with precise molecular sieving for antibiotic desalination.

纳滤膜（NF）因其节能环保的特点，在离子分离和抗生素纯化方面发挥着至关重要的作用。然而，由于缺乏内在刚性微孔，传统的聚合物膜很容易在渗透性和选择性之间 "权衡利弊"。在此，我们合成了具有不同空腔尺寸的氨基环糊精（amino-CDs），并将其用作构建 15 纳米厚纳米膜的构件。在纳米薄膜中合理加入具有明确定义和可调空腔的大环，可显著提高透水性，并精确控制膜的分子量截断。由于离子通过 CD 空腔的固有能障存在显著差异，CD 导入膜的 Cl-/SO42- 选择性高达 87。此外，经 CD 调节的膜显示出卓越的抗生素脱盐性能，优于最先进的抗生素纯化膜。这项研究为开发用于抗生素脱盐的具有精确分子筛分功能的纳滤膜提供了一个途径。

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引用次数: 0

Non-metallic cation and anion co-doped perovskite oxide ceramic membranes for high-efficiency oxygen permeation at low temperatures 用于低温下高效氧气渗透的非金属阳离子和阴离子共掺杂过氧化物陶瓷膜

IF 8.4 1区工程技术 Q1 ENGINEERING, CHEMICAL

Journal of Membrane Science

Pub Date : 2024-11-13 DOI: 10.1016/j.memsci.2024.123500

Song Lei , Sisi Wen , Jian Xue , Ao Wang , Jiaqi Li , Zhongyuan Liu , Longgui Zhang , Yifeng Li , Haihui Wang

Insufficient structural stability and limited lattice oxygen mobility at low temperatures seriously limit the application of perovskite-type oxides in mixed ionic-electronic conducting oxygen-permeable membranes. Engineering the crystal structure and oxygen vacancies by ion doping is an effective strategy to enhance both structural stability and lattice oxygen mobility. Different from conventional metal ion doping, we report that the co-doping of the classical SrCoO_3-δ by the non-metallic cation P⁵⁺ and the anion Cl⁻ stabilizes the cubic perovskite structure and allows low temperature oxygen permeation due to improved lattice oxygen mobility. In detail, P doped at the Co site transforms the crystal structure from the hexagonal phase to the cubic phase, and Cl doped at the oxygen site weakens the metal-oxygen bond, which significantly enhances the lattice oxygen mobility. Optimal doping concentrations were found to be SrCo₀_.₉₅P₀_.₀₅O_3-δCl_0.05 (SCP5Cl5). Furthermore, by constructing an asymmetric membrane with a sandwich structure, the oxygen permeation flux of the SCP5Cl5 ceramic membrane was up to 1.10 mL min⁻¹ cm⁻² at 873 K, which provides an effective strategy for developing oxygen-permeable membranes with high permeation flux at low temperatures.

结构稳定性不足和低温下有限的晶格氧迁移率严重限制了透氧膜中包晶型氧化物的应用。通过离子掺杂对晶体结构和氧空位进行工程化处理是提高结构稳定性和晶格氧迁移率的有效策略。与传统的金属离子掺杂不同，我们报道了非金属阳离子 P5+ 和阴离子 Cl- 共同掺杂经典的 SrCoO3-δ 可稳定立方包晶结构，并通过改善晶格氧迁移率实现低温透氧。具体来说，掺杂在 Co 位点的 P 可使晶体结构从六方相转变为立方相，而掺杂在氧位点的 Cl 可减弱金属-氧键，从而显著提高晶格氧迁移率。最佳掺杂浓度为 SrCo0.95P0.05O3-δCl0.05（SCP5Cl5）。此外，通过构建具有三明治结构的不对称膜，SCP5Cl5 陶瓷膜在 873 K 时的氧气渗透通量高达 1.10 mL min-1 cm-2，这为开发低温高渗透通量透氧膜提供了一种有效的策略。

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引用次数: 0

New insight into pore characteristics for cake layers formed on nanocomposite membranes: Effect of membrane surface fractality 对纳米复合膜上形成的滤饼层孔隙特征的新认识：膜表面断裂的影响

IF 8.4 1区工程技术 Q1 ENGINEERING, CHEMICAL

Journal of Membrane Science

Pub Date : 2024-11-13 DOI: 10.1016/j.memsci.2024.123498

Juan Tang , Mengqi Zhang , Kang Liu , Fang Zhang , Haiou Huang

Over the past two decades, there has been extensive research that attempts to relate membrane's performance to its surface roughness. However, applicability of this approach to nanocomposite membranes is questionable, given the highly diverse membrane structures. In this study, three types of carbon nanotube composite membranes (CNT_S, CNT_M, and CNT_L) were prepared and used to filter fluorescent polystyrene particles under favorable surface interaction conditions. The resulting cake structures were imaged using laser confocal microscopy and analyzed for pore characteristics. It was found that cake layers with lower porosity and smaller average pore size also had more tortuous and complex pore channels, leading to lower water permeability. Moreover, simulations of the cake layers with a pore network model reveal that pore radius and throat length are key factors affecting water permeability. Further application of the machine learning (ML) model accurately predicts cake permeability based on the 3D fractal dimension (2.44–2.81), anisotropy (0.64–0.81) and porosity (0.3–0.71) of the pore space and R² of the test set reaches 0.96. Finally, the Weierstrass-Mandelbrot equation is applied to describe the self-similar fractal surfaces possessed by the CNT membranes. The respective fractal dimensions of three membrane surfaces (D_f) are 2.31, 2.11 and 2.57. At a D_f value of 2.31, the cake layer exhibits greater pore homogeneity and connectivity, and thus higher water permeability. Overall, this study revealed the fractal nature of CNT membrane surface and its relevance to pore structure and water permeability of the cake layers.

在过去二十年里，有大量研究试图将膜的性能与其表面粗糙度联系起来。然而，鉴于膜结构的高度多样性，这种方法是否适用于纳米复合膜尚存疑问。本研究制备了三种碳纳米管复合膜（CNT_S、CNT_M 和 CNT_L），并在有利的表面相互作用条件下用于过滤荧光聚苯乙烯颗粒。使用激光共聚焦显微镜对所得滤饼结构进行成像，并分析其孔隙特征。结果发现，孔隙率较低、平均孔径较小的滤饼层具有更曲折、更复杂的孔道，从而降低了透水性。此外，利用孔隙网络模型模拟滤饼层时发现，孔隙半径和喉管长度是影响透水性的关键因素。进一步应用机器学习（ML）模型，根据孔隙空间的三维分形维数（2.44-2.81）、各向异性（0.64-0.81）和孔隙度（0.3-0.71）准确预测了滤饼的透水性，测试集的 R2 达到 0.96。最后，应用魏尔斯特拉斯-曼德尔布罗方程来描述 CNT 膜所具有的自相似分形表面。三个膜表面的分形维数（Df）分别为 2.31、2.11 和 2.57。当 Df 值为 2.31 时，滤饼层表现出更高的孔隙均匀性和连通性，因此透水性更高。总之，这项研究揭示了 CNT 膜表面的分形性质及其与滤饼层孔隙结构和透水性的相关性。

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引用次数: 0

Achieving antibiofouling on microporous membranes prepared with a green solvent via spraying an aqueous antifouling copolymer solution 通过喷洒防污共聚物水溶液实现用绿色溶剂制备的微孔膜的防污效果

IF 8.4 1区工程技术 Q1 ENGINEERING, CHEMICAL

Journal of Membrane Science

Pub Date : 2024-11-12 DOI: 10.1016/j.memsci.2024.123499

Trisha Nicole Lazo , Irish Valerie Maggay , Lemmuel Tayo , Yung Chang , Antoine Venault

This study highlights a comprehensive investigation into the fabrication and characterization of sustainable membranes for antifouling applications. It utilizes γ-valerolactone as a green solvent to obtain microfiltration polyvinylidene difluoride (PVDF) membranes, and leverages spray-coating technique to modify these membranes. This research aims to enhance the surface and bulk properties of PVDF membranes while promoting sustainable practices. Chemical analyses of the membranes reveal that the surface and bulk of the membranes were successfully modified. Dynamic water contact angle measurements indicated that a 10 mg/mL coating solution (PVDF_10) resulted in the highest hydrophilicity. Different biofouling tests were conducted using proteins and bacteria. In adhesion tests with BSA, and E. coli, the PVDF_10 membrane demonstrated the highest resistance, reducing adhesion by approximately 83 % and 94 %, respectively. Additionally, cyclical water/bacterial filtration tests demonstrated that PVDF_10 membrane achieved a higher flux recovery ratio compared to commercial hydrophilic PVDF membranes. The modification remained stable even after 6 weeks of immersion in water. This study highlights the potential of γ-GVL and the spray-coating technique as environmentally friendly solvents and modification techniques for producing green antifouling PVDF membranes, aligning with sustainable practices and significantly enhancing membrane performance.

本研究重点介绍了用于防污应用的可持续膜的制造和表征的综合调查。它利用γ-戊内酯作为绿色溶剂，获得微过滤聚偏二氟乙烯（PVDF）膜，并利用喷涂技术对这些膜进行改性。这项研究旨在提高聚偏二氟乙烯（PVDF）膜的表面和体积性能，同时促进可持续发展。对膜的化学分析显示，膜的表面和主体均已成功改性。动态水接触角测量表明，10 毫克/毫升的涂层溶液（PVDF_10）具有最高的亲水性。使用蛋白质和细菌进行了不同的生物污损测试。在使用 BSA 和大肠杆菌进行的附着测试中，PVDF_10 膜表现出最高的抗性，分别减少了约 83% 和 94% 的附着力。此外，循环水/细菌过滤测试表明，与商用亲水性 PVDF 膜相比，PVDF_10 膜的通量回收率更高。即使在水中浸泡 6 周后，这种改性仍能保持稳定。这项研究强调了 γ-GVL 和喷涂技术作为环保型溶剂和改性技术在生产绿色防污 PVDF 膜方面的潜力，既符合可持续发展的做法，又能显著提高膜的性能。

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引用次数: 0

Overall mass transfer approach for electrodialysis-based acid recovery 基于电渗析的酸回收的整体传质方法

IF 8.4 1区工程技术 Q1 ENGINEERING, CHEMICAL

Journal of Membrane Science

Pub Date : 2024-11-12 DOI: 10.1016/j.memsci.2024.123495

Xiao-guang Xu , Yu-xiang Jia , Meng Wang

The reclamation of low-concentration waste acid (e.g., pH > 0.5) has garnered significant attention due to its prevalence, substantial output, and considerable potential value. Notably, a further concentration of the separated acid is typically required for practical applications, for which electrodialysis (ED) has been widely acknowledged as an effective method. However, various factors, including proton leakage, complicate the application of ED in acid systems compared to salt systems. This study presents a novel modeling approach for ED-based acid recovery utilizing the overall mass transfer (OMT) methodology for the first time. Importantly, regression models incorporating initial concentration and current density as independent variables have been developed to calculate the OMT coefficients and cell resistance following a quantitative analysis of the effects of acid media and electric field on mass transport phenomena, based on a series of carefully designed experiments. Subsequent predictions regarding a typical ED-based acid recovery process were conducted, yielding results that align closely with experimental data. For instance, the relative deviations for concentration and volume evolution were found to be less than ±8.4 % and ±7.9 %, respectively. Additionally, the relative deviations for energy consumption were recorded at 8.2 % and 3.2 % for the overall process and the ED stack, respectively. Furthermore, simulations were performed to evaluate the impacts of operational conditions on ED performance using the derived models. In conclusion, the efficacy of the OMT approach for modeling the ED process in acid systems has been substantiated. It is reasonable to assert that the developed models will be beneficial for production management and the optimization of operating conditions in ED-based acid recovery processes.

低浓度废酸（如 pH 值为 0.5）的回收利用因其普遍性、可观的产量和巨大的潜在价值而备受关注。值得注意的是，在实际应用中，分离出的酸通常需要进一步浓缩，而电渗析（ED）已被公认为是一种有效的方法。然而，与盐系统相比，包括质子泄漏在内的各种因素使电渗析在酸系统中的应用变得更加复杂。本研究首次利用整体传质（OMT）方法为基于电渗析的酸回收提供了一种新型建模方法。重要的是，在对酸介质和电场对质量传输现象的影响进行定量分析后，基于一系列精心设计的实验，开发了将初始浓度和电流密度作为自变量的回归模型，用于计算 OMT 系数和电池电阻。随后对典型的基于电解质的酸回收过程进行了预测，结果与实验数据非常吻合。例如，浓度和体积演化的相对偏差分别小于 ±8.4 % 和 ±7.9%。此外，整个过程和 ED 堆的能耗相对偏差分别为 8.2 % 和 3.2 %。此外，还利用推导出的模型进行了模拟，以评估运行条件对 ED 性能的影响。总之，OMT 方法对酸系统中 ED 过程建模的有效性已得到证实。可以合理地断言，所开发的模型将有助于基于 ED 的酸回收工艺的生产管理和操作条件优化。

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引用次数: 0

Highly efficient porous MXene desalination membranes controlled by the thickness of the transition metal carbides 由过渡金属碳化物厚度控制的高效多孔 MXene 海水淡化膜

IF 8.4 1区工程技术 Q1 ENGINEERING, CHEMICAL

Journal of Membrane Science

Pub Date : 2024-11-10 DOI: 10.1016/j.memsci.2024.123468

Ting Si , Xinyao Ma , Zhenyu Liao , Huan Chen , Bochun Liang , Sai Tak Chu , Jun Fan

MXene membrane has the vast potential to alleviate the global freshwater crisis. Herein, a new strategy for improving the desalination performance is proposed through tunable the thickness transition metal carbides of the nano-porous MXene membrane. The thickness of porous MXene is investigated by molecular dynamics (MD) simulation, including the Ti₂CF₂, Ti₃C₂F₂, and Ti₄C₃F₂. The results show that the porous MXene membrane can reach highly efficient desalination. The water density distribution reveals that more water gathers in the thicker transition metal carbides layer, contributing to the poor water flux; the average charge distribution indicates that the transition metal layer plays an essential role in effectively rejecting Na⁺/trapping Cl⁻ ions. Multilayered porous membranes are explored to improve the trade-off desalination performance. The number of pores enhances the water permeability, and the multilayers improve the ion rejection. The two-layered Ti₃C₂F₂ membrane with three nanopores achieves nearly doubled water flux and keeps 100 % ion rejection. Our work reported that the nano-porous MXene membrane offers a prospective strategy to eliminate the current design defects, which provides an innovative method for the desalination semipermeable membrane industry.

MXene 膜具有缓解全球淡水危机的巨大潜力。本文提出了一种通过调节纳米多孔 MXene 膜的过渡金属碳化物厚度来提高海水淡化性能的新策略。通过分子动力学（MD）模拟研究了多孔 MXene 的厚度，包括 Ti2CF2、Ti3C2F2 和 Ti4C3F2。结果表明，多孔 MXene 膜可以实现高效脱盐。水密度分布表明，更多的水聚集在较厚的过渡金属碳化物层中，导致水通量较差；平均电荷分布表明，过渡金属层在有效排斥 Na+ 离子/捕获 Cl- 离子方面起着至关重要的作用。多层多孔膜被用来改善海水淡化性能。孔隙数量可提高透水性，而多层膜则可改善离子阻隔性。具有三个纳米孔的双层 Ti3C2F2 膜实现了近两倍的水通量，并保持了 100% 的离子抑制率。我们的工作表明，纳米多孔 MXene 膜为消除现有设计缺陷提供了一种前瞻性策略，为海水淡化半透膜行业提供了一种创新方法。

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