耐溶剂纳滤膜研究进展

纳滤的诸多优点使其在有机溶剂体系中具有极大的潜在应用价值,耐溶剂纳滤膜(SRNF)的制备是有机溶剂纳滤发展的关键。本文从耐溶剂纳滤膜材料出发,综述了耐溶剂纳滤膜的制备及应用等方面的研究进展。重点介绍了均相膜、复合膜等多种耐溶剂纳滤膜材料及制备方法,并对今后研究的发展方向提出建议。     

耐溶剂高分子纳滤膜研究进展

纳滤的诸多优点使其在非水溶液体系中具有极大的潜在应用价值,本文从耐溶剂高分子纳滤膜材料出发,综述膜材料化学结构对膜性能、形态等各方面的影响.认为研究和发展耐溶剂纳滤膜,对生物、医药、石油化工和食品等行业的发展有着重要的意义.     

耐溶剂复合纳滤膜的研究进展

耐溶剂纳滤是一种新型的膜分离技术,用于有机混合物的分离。商品耐溶剂纳滤膜大多是采用相转化法制备的整体皮层非对称膜,膜皮层较厚,通量较低。耐溶剂复合纳滤膜由基膜和分离层组成,具有薄皮层、高溶剂通量和高溶质截留率的优点。耐溶剂复合纳滤膜的制备与改性也因此成为近年来的研究热点。本文从界面聚合、表面涂覆、层层自组装、原位生长、有机-无机杂化和表面改性六个方面介绍耐溶剂复合纳滤膜的研究进展,最后对其发展前景进行展望。     

芳香聚酰胺纳滤膜的制备及性能研究

以芳香聚酰胺为原料,采用相转化法制备了芳香聚酰胺纳滤膜,通过正交试验确定了最佳制膜工艺.详细讨论了纳滤膜的分离特性,并对纳滤膜的耐溶剂及抗污染性能进行了初步研究.实验结果表明,所制芳香聚酰胺纳滤膜对无机盐及小分子有机物具有较好的选择分离性能.操作压力为0.4MPa时,该膜对蔗糖的截留率为63.74%,对葡萄糖的截留率为54.36%.膜具有很好的耐溶剂性和抗污染性.     

耐溶剂纳滤膜的制备与应用研究进展

有机溶剂纳滤(organic solvent nanofiltration,OSN)是近年来快速发展起来的一项新型纳滤膜分离技术,具有广阔的应用前景。耐溶剂纳滤(solvent-resistant NF,SRNF)膜的制备是OSN技术发展的关键,也是目前的研究热点之一。本文侧重阐述了SRNF膜在制备及应用方面的进展,着重介绍了相转化法、界面聚合法、自组装法及有机-无机杂化法等SRNF膜制备方法。相转化法是目前国内外SRNF膜制备研究常用的方法,但该法所制备的膜皮层较厚,通量明显偏小;界面聚合法SRNF膜制备的相关研究目前较少,但由于其皮层非常薄,因此是SRNF膜制备发展的一大趋势;自组装膜有较好的耐溶剂性能;加入无机物可以提高耐有机溶剂性,有机-无机杂化法的膜制备是SRNF膜制备的趋势之一。同时简单介绍了SRNF膜的应用,并对未来SRNF膜研究的方向提出了建议。     

pH响应型高分子膜的制备与应用研究进展

pH响应型高分子膜即膜的体积、膜孔径、渗透通量、截留率等能够根据环境pH的变化而变化的分离膜。对几年来pH响应型高分子膜的制备方法进行归纳,总结了其在金属离子脱除、蛋白质分离、药物控制释放及耐溶剂性分离膜方面的应用。     

纳滤膜分离技术及其进展

纳滤技术是一种介于超滤和反渗透之间的新型分离技术。作者介绍了纳滤膜的特性及其独特的分离特点。高分子纳滤膜的几种主要制备方法的制备原理、制备要点,国内外纳滤膜在生产研究方面的进展,以及当前已商品化的几种主要的纳滤膜的材质。最后简单介绍了纳滤膜在水处理、食品、生化、医药、染料和化工等领域的应用进展,指出今后的发展将着重于传质机理、新的膜材料及集成工艺开发等方面。     

有机溶剂纳滤传递模型及最新膜材料研究进展

有机溶剂纳滤（organic solvent nanofiltration, OSN）是一种高效节能、操作简便的新型膜分离技术,在化工、制药、能源和环境等相关领域具有广阔的应用前景,因此受到了膜技术领域内研究者们的重点关注。本文首先简述了有机溶剂纳滤的应用背景,其次从有机溶剂纳滤传递模型与膜材料两个方面,总结归纳了近年来在有机溶剂纳滤领域取得的研究进展。总结了基于无机陶瓷、高分子聚合物、多孔有机聚合物、有机-无机杂化材料以及石墨烯类二维材料等用于制备新型OSN膜的研究进展,并结合传输模型讨论分析了有机溶剂分子在膜内的传输行为及膜的分离性能。最后简述了有机溶剂纳滤技术在化工及相关行业中的应用现状,并指出了这些关键有机溶剂纳滤膜材料在有机溶剂纳滤应用中存在的优势和挑战,提出了基于这些关键材料的特点进行设计和优化OSN膜性能的建议供参考,以期促进有机溶剂纳滤膜的研究和应用。     

新型纳滤膜材料研究进展

简单阐述了纳滤膜的特点及应用范围,重点分类介绍了近年来一系列新型纳滤膜材料及其性质与研究成果,包括有机高分子膜材料、有机-无机矿物膜和无机陶瓷膜材料三大类,分别列举各类材料的典型膜,对各种膜的性能参数和主要制备方法进行了对比总结,并对膜材料今后的发展前景作了展望。     

纳滤膜技术及其应用

介绍了纳滤及纳滤膜的特性、不同构型的膜的制备以及纳滤膜的制备工艺和组件的制造要求,简述了纳滤膜的几种分离机理,并对纳滤膜技术在饮用水及废水处理等方面的应用进展进行了综述。     

巡视中空纤维膜的研发和产业进展

介绍了国内外用于人工肾的中空纤维透析膜、用于废水处理的微滤、超滤中空纤维及膜生物反应器（MBR）、用于海水淡化的中空纤维反渗透膜、用于气体分离及有机物代精馏的中空纤维膜、用于双亲和性吸附蛋白质的固定双配合剂多微孔中空纤维膜、用于回收海水资源的微滤和纳滤膜、用于脱氧核糖核酸链（DNA）切片的内含亲水性聚合物的中空纤维膜以及新型电池隔膜.     

纳滤膜在功能性低聚糖分离纯化中的应用研究进展

功能性低聚糖具有抗肿瘤、抗放射、抗凝血、消炎和调节免疫力等医疗保健作用,广泛应用于食品科学和生物医药等领域。纳滤作为一种高效的膜分离技术,在功能性低聚糖的分离与纯化中的应用得到越来越多的关注。本文分析了纳滤膜对功能性低聚糖的分离机理,综述了纳滤膜在功能性多糖分离纯化中的应用进展,讨论了纳滤分离过程的影响因素,主要包括功能性多糖料液的性质、膜过程的操作参数以及膜材料本身的性质等。其中,料液的性质主要体现在组成、浓度、黏度等方面;操作参数主要体现在压力、温度、膜面流速和pH等方面;而膜材料的性质主要体现在微结构和表面性质两个方面。最后,进一步指出纳滤膜技术用于功能性多糖分离纯化时在设备成本、膜材料及膜污染等方面存在的问题,并对未来纳滤膜技术在低成本专用膜材料及系统开发和膜污染控制方面的研究进行了展望。     

Comparison Between Polydimethylsiloxane and Polyimide-Based Solvent-Resistant Nanofiltration Membranes

Nanofiltration using solvent-resistant membranes has become an important separation technology. Polydimethylsiloxane and polyimide are important materials for preparation of solvent-resistant nanofiltration (SRNF) membranes. In this study, the performance of commercial polydimethylsiloxane and polyimide SRNF membranes (as a trademark of MPF and STARMEM) with molecular weight cutoff values of 200–700 Da was compared in terms of organic solvent preconditioning effect, solvent compatibility, solvent flux, and solute rejection. Organic solvents employed were methanol, toluene, ethyl acetate, dichloromethane, and acetone and the organic solutes in a molecular weight range of 160–850 Da were used. Membrane preconditioning with different organic solvents did not affect membrane performance of the polydimethylsiloxane-based MPF membranes but had a significant influence on the polyimide-based STARMEM membranes. Both MPF and STARMEM membranes are not compatible in dichloromethane. MPF membranes were inert to the organic solvents and had relatively low solvent fluxes. STARMEM membranes were highly swollen in methanol and offered much higher solvent fluxes and attractive NF performance in toluene.     

Polyaromatics

The polyaromatics are an important group of industrial polymers. For the highest performance applications the polyaryletherketones and polyarylethersulphones have proved very effective and have been successfully commercialised. Both polymer types, but mainly polyetheretherketone (Victrex PEEK), have been subjected to intense academic and industrial research in respect of their physical and chemical properties, thermal stability, irradiation resistance and their application in engineering and composite matrices. The synthesis of these polyaromatics has been widely studied but the nucleophilic polycondensation route is proving to be the only commercially viable one. Block copolymers have been synthesised, using transetherification to randomise polyaryletherketone-co-sulphone backbones as well as by utilising the reactive polymer end-groups, and studied in considerable detail to establish structure–property relationships. Such end-groups on arylethersulphone-type polymers have also been used effectively in the development of tough, solvent-resistant and easily processable thermoset–thermoplastic blends for use, in particular, as composite matrices. Pendant functionality has been studied as a route to improved properties and solvent resistance and is used commercially in the manufacture of polymers for membranes.     

Investigation of combined fouling behavior in nano-filtration process under various feed conditions

Despite the great advance in nano-filtration (NF) process development in various applications, its performance in water treatment is still impeded by the undesired fouling phenomenon, which is not yet fully understood nowadays. In this study, a comprehensive investigation on the fouling behavior, more specifically the combined fouling behavior with the presence of more than one type of foulant was carried out under various solution chemistries and feed hydraulic pressures. The interaction between the model organic foulant (alginate) and inorganic foulant (silica colloid) was systematically studied with nano-filtration membranes, with a more severe fouling observed in the combined fouling than individual foulants. However, the results also revealed that the commonly observed synergistic effect of combined fouling in the forward osmosis process was not present in the nano-filtration process. In addition, the solution chemistries (pH and calcium ions) and feed hydraulic pressure were also found to have certain influence on the combined fouling, especially the feed hydraulic pressure which exhibited a more pronounced impact on the flux decline than the other factors, thus in turn, affecting more on the reversibility of the membrane fouling.     

Molecular dynamics simulation for investigating and assessing reaction conditions between carboxylated polyethersulfone and polyethyleneimine

Recently, nano-filtration membranes are made by the reaction between a reactive functional group on the surface of a tight ultrafiltration membrane and a charged branched polymer. This reaction makes the selective layer of the nanofiltration membrane, which plays an essential role in membrane performance. A molecular dynamics simulation with a reactive force field was used to investigate the reaction of carboxylated polyethersulfone as the functional group of the ultrafiltration membrane with polyethyleneimine. Experimental elucidation of the reaction between the PEI amine and carboxyl groups is challenging, and an MD simulation was thus employed. Furthermore, the simulation results show that the PEI and carboxylated polyethersulfone polymers react with each other in a temperature-dependent manner. While no reaction occurs at 298 K, carboxylated polyethersulfone and PEI begin to react when the temperature is increased from 298 to 323 K. Furthermore, a reversible reaction was observed with a subsequent increase in temperature to 353 K.     

纳米膜法过滤脱氯淡盐水中SO42-的应用研究

针对采用纳米膜过滤脱氯淡盐水中SO42-装置运行中的具体问题,结合纳米膜过滤脱氯淡盐水中SO42-生产装置的实际运行数据与纳米膜过滤运行特点,对纳米膜过滤装置应用情况分时间段进行了分析研究,从而总结出了纳米膜过滤技术实际应用过程中的一些变化规律,找出了提高纳米膜过滤脱氯淡盐水中SO42-装置能力的有效措施。     

Polymer-based membranes for solvent-resistant nanofiltration:A review

Separation of organic mixture is an inevitable process in most modern industrial processes. In the quest for a more sustainable and efficient separation, solvent-resistant nanofiltration (SRNF) has emerged as a promising answer. This is because SRNF is a membrane-based process which offers the key advantages of high efficacy and lowenergy intensity separation. In particular, polymer-based membranes can offer compelling opportunities for SRNFwith unprecedented cost-effectiveness.As a result, intensive research efforts have been devoted into developing novel polymer-based membraneswith solvent-resistant capacities as well as exploring potential applications in different types of industries. In this review, we aim to give an overview of the recent progress in the development of the state-of-the-art polymer-based membranes for SRNF in the first section. Emerging nanomaterials for mixed matrix and thin film nanocomposite membranes are also covered in this section. This is followed by a discussion on the current status ofmembrane engineering and SRNFmembrane commercialization. In the third section,we highlight recent efforts in adopting SRNF for relevant industrial applications such as food, bio-refinery, petrochemical, fine chemical and pharmaceutical industries followed by separations of enantiomers in stereochemistry, homogeneous catalysis and ionic liquids. Finally, we offer a perspective and provide deeper insights to help shape future research direction in this very important field of SRNF.