油水分离膜表面结构可控合成及性能研究

石油开采过程中会产生大量的油水混合物,每天生产生活中也会产生大量含油废水,如何处理这些油水混合物,是环境保护和可持续发展的重大需求。针对含油量较高的油水混合物,本工作制备了疏水-超亲油分离膜。以机械性能较好的泡沫镍为过滤基体,采用电沉积方法,在泡沫镍表面沉积铜颗粒,构筑亲油疏水表面。研究了沉积电位和沉积时间对表面结构的影响,并测试了分离膜表面结构、表面粗糙度及水滴在膜表面的接触角,并对所制备的分离膜进行油水分离性能测试和多次循环的稳定性测试。结果表明,所制备的分离膜具有良好的循环分离性能,对于油水混合物循环十次后分离效率仍在90%以上。本研究为高效油水分离膜材料开发提供了新思路,并拓展了电化学表面改性的应用领域。     

耐腐蚀超疏水超亲油不锈钢网的制备及其在油水分离过程中的应用

以不锈钢网为基底,通过化学刻蚀法制备微米级粗糙表面,通过一步浸泡法将st9ber法制得的疏水亲油纳米Si O2颗粒沉积到粗糙的不锈钢网表面,制备了具有微纳二级粗糙结构的超疏水超亲油不锈钢网。利用扫描电子显微镜(SEM)、傅里叶变换红外光谱仪(FT-IR)和接触角测量仪(CA)表征了超疏水超亲油不锈钢网的表面形貌、化学组成和润湿性能,并将其用于油水分离过程中。结果表明,疏水亲油纳米Si O2颗粒成功的沉积到不锈钢网表面;水滴在超疏水超亲油不锈钢网上的接触角最大为151°,煤油的接触角为0°;制备的超疏水超亲油不锈钢网不仅能高效的分离不同种类油和水的混合物,还能高效的分离油和腐蚀性液体(强酸或强碱水溶液)的混合物,其耐腐蚀特性可满足复杂环境下的油水分离要求。     

超疏水三维多孔材料在乳化液油水分离中的应用研究进展

超疏水三维多孔材料基于润湿性和毛细作用可有效吸附回收水中浮油,近年来在乳化液的油水分离中也得到应用。本文重点从超疏水三维多孔材料的设计制备、对乳化液的油水分离效果、油滴在材料中的分离机制3个方面展开分析与评价。文中指出：材料设计制备方面,以海绵为主的多孔材料主要通过修饰低表面能物质和构建粗糙结构获得超亲油疏水性,疏水改性后的材料具备较高的油吸附容量（31～131g/g）。乳化液油水分离评价方面,超疏水三维多孔材料处理的对象多为O/W模型乳化液,油浓度低、表面活性剂浓度低、液滴粒径为微米级,少见对实际乳化液的处理;应用方式包括基于吸附作用的浸泡处理和吸附协同拦截作用的过滤处理两类;分析发现影响油水分离效果的关键是材料的孔径、表面疏水性和带电性。作用机制方面,疏水多孔材料吸附乳化油的作用过程仍停留在理论推测层面,主要观点为材料通过笼状孔道结构和疏水表面高效捕集和吸附油滴,油滴聚并破乳形成油层而被分离。虽然超疏水三维多孔材料在乳化液油水分离应用研究中取得了一定进展,但仍需探究其对实际废乳化液的适用性,设计开发连续分离设备以实现工程应用;结合原位观测、数值模拟、力学解析等方法解析油滴在多孔材料...     

PVA型超亲水-水下超疏油过滤膜油水分离性能研究

稀土萃取分离生产过程中会产生大量的含油废水亟待处理，超亲水-水下超疏油过滤膜为稀土冶炼含油废水带来了新的解决方案。以过滤棉为基材，以富含羟基的聚乙烯醇(PVA)与亲水的纳米二氧化硅溶胶为前驱体，以戊二醛为交联剂制备了PVA型超亲水-水下超疏油过滤膜。接触角测试表明，在空气介质中对水的接触角为0°，在水介质中对油的接触角为155.3°，具备优良的超亲水-水下超疏油性能。对制备的PVA型超亲水-水下超疏油过滤膜进行油水分离实验发现，3次重复实验过滤膜的平均油水分离率为97.5%，膜通量为11.89 L/(m²·s)，经30次油水分离循环测试，该过滤膜仍具有95.3%的油水分离率和11.06 L/(m²·s)的膜通量，展现了较好的耐久性和稳定性，具有一定的工业推广应用前景。     

油水分离膜的研究进展

介绍了油水混合物的分类、油水分离膜的分离机理、油水分离膜的类型以及超疏水-亲油膜、超亲水-疏油膜的制备和性能。根据油水分离膜技术现在的发展状况,指出目前在该领域的研究中存在的一些问题以及对未来的发展趋势进行了展望。超疏水-亲油膜从材料制备和油水分离性能等方面,均取得了长足发展,但该膜的疏水稳定性和膜材料的力学强度等有待进一步提高。超亲水-疏油膜的制备过程简单、性能稳定、易清洗,近年来被广泛应用。     

纳米材料在油水分离应用方面的研究进展

油水分离是当前处理处置各类含水工业废油,修复环境水体油液污染的关键技术;而纳米技术的快速发展已经在各个领域,包括能源、环境及医学等领域发挥着巨大的作用。利用纳米材料的特殊性质结合传统材料的特点制作超疏水-超亲油性、超亲水-超疏油材料用于油水分离是目前的研究热点之一,具有广阔的应用前景。综述了近几年来纳米材料在油水分离应用方面的研究进展,主要介绍了超疏水、超亲水、磁性等几种主要的纳米材料的制备,油水分离的效率,适用范围等。综述有望为开发高效的油水分离技术和设计新型分离材料提供技术参考。     

纳米材料在油水分离应用方面的研究进展

油水分离是当前处理处置各类含水工业废油,修复环境水体油液污染的关键技术;而纳米技术的快速发展已经在各个领域,包括能源、环境及医学等领域发挥着巨大的作用。利用纳米材料的特殊性质结合传统材料的特点制作超疏水-超亲油性、超亲水-超疏油材料用于油水分离是目前的研究热点之一,具有广阔的应用前景。综述了近几年来纳米材料在油水分离应用方面的研究进展,主要介绍了超疏水、超亲水、磁性等几种主要的纳米材料的制备,油水分离的效率,适用范围等。综述有望为开发高效的油水分离技术和设计新型分离材料提供技术参考。     

疏水亲油分离膜的润湿性研究进展

疏水亲油分离膜通过透过油相、截留水相而实现油水分离过程,它具有绿色、高效、易于工业放大等特点,在环境保护、水处理、有机液体分离与回收等领域具有广阔的应用前景,已成为膜科学与技术领域的研发热点。本文回顾了润湿方程的发展历史,介绍了表面润湿性和孔径的协同作用对膜分离过程的影响,讨论了疏水亲油分离膜的设计策略,包括在低表面能材料的表面构建粗糙或微纳米结构和使用低表面能材料对粗糙表面进行疏水改性。最后,对疏水亲油分离膜的发展趋势进行了展望,今后需进一步完善表面浸润理论,开发易于工业生产的制膜方法,探究疏水亲油分离膜对复杂油水混合物（如高黏度、多组分）的分离效果。     

宁波材料所制备出高效油水分离用纤维素海绵

<正>近年来,超疏油-超亲水材料由于其特殊的润湿性在油水分离方面备受青睐。由于"油"的表面张力远小于水,故超疏油-超亲水表面较难制备而且超疏油表面大多超疏水,这就限制了其在油水分离方面的应用。此外,表面活性剂稳定的乳化油油滴粒径小(10μm)、稳定性高,需要复杂的破乳过程才能实现油水分离。所以,亟需一种简单、高效、环境友好的油水分离材料来实现含油污水的净化处理。中国科学院宁波材料技术与工程研究所科研人员曾志翔、王刚、贺怡等通过纤维素的溶解再生及成孔剂     

新型的纤维-液膜油水分离器

介绍一种新型的纤维 液膜油水分离设备 ,主要由聚结罐和分离罐组成 ,采用改性强亲油性纤维作为聚结罐内件 ,使含油污水中的细小油滴通过强亲油性纤维在较短的时间内合并为大油滴成为可能 ,缩短分离罐沉降时间 ,提高油水分离效率。试验表明 ,新型的纤维 液膜油水分离设备用于处理含油污水是行之有效的 ,用于处理稀油污水比稠油污水效果更好     

Hierarchical amphiphilic high-efficiency oil–water separation membranes from fermentation derived cellulose and recycled polystyrene

A high-efficiency separation of oil and water can be achieved by using specially designed amphiphilic porous membrane. However, the preparation of such membranes often involves complex multistep chemical processes. Herein, we report an amphiphilic composite membrane (polystyrene [PS]/bacterial cellulose [BC] membrane) consisting of hydrophobic recycled PS and hydrophilic BC, fabricated by a facile in situ fermentation process. Not only these membranes exhibit a combination of contrasting wettability but also comprise of a hierarchical network of microfibers and nanofibers, which makes them ideal for oil–water separation. The structural and morphological properties of as-produced BC, recycled PS membrane, and PS/BC composite membrane were studied by Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. The ability of the membranes to separate oil and water was tested by using an emulsion of hexane-in-water as the feed and the collected filtrates were characterized by optical microscopy and UV–Vis spectroscopy. PS membranes were unable to separate oil and water, while the PS/BC membrane efficiently separated water from the emulsion. PS/BC composite membranes showed a high water recovery of more than 90%, against only 57% recovery shown by BC. Mechanisms of oil–water separation for each membrane are discussed. The reusability of the PS/BC composite membrane was also demonstrated.     

Recent advances in membrane hydrophilic modification with plant polyphenol-inspired coatings for enhanced oily emulsion separation

Oily wastewater, especially the emulsified one, causes serious environment pollution and poses threats to the ecosystem and resource recycling. Among various filtration media, porous polymeric membranes have gained tremendous attention in dealing with oily emulsions due to their energy-saving, cost-effective, and highly efficient features. However, to alleviate membrane fouling by oil droplets and ensure high separation efficiency, endowing membrane with superhydrophilicity and underwater superoleophobicity via facile strategy is highly desired. Taking advantages of the mild forming conditions, universality and cost-efficiency, more and more efforts have been devoted to membrane hydrophilic modification by plant polyphenol-inspired coatings in recent years. In this review, we focus on recent advances in constructing plant polyphenol-involved coatings on membrane surface for oil-in-water emulsion separation. The interactions between plant polyphenol and functional materials including amino-functionalized materials, transition metal ions and oxidants via covalent chemistry, coordination chemistry, and rapid oxidation are highlighted. In addition, the impacts of the resultant coating on the wettability, oily emulsion separation performance, and anti-oil fouling performance of the modified membrane are systematically summarized. Finally, future outlooks in membrane surface engineering with plant polyphenol-involved coatings are discussed to further broaden the research related to high-efficiency oil/water separation based on membrane technology.     

Effiziente Wasserabtrennung aus Dieselkraftstoff mittels Membrantechnik und Online‐Monitoring

The separation of water from diesel fuel is very important for safety, ecological, and economic reasons, as otherwise it can lead to lower combustion efficiency and engine problems. In addition, the free water from ultra‐low‐sulfur diesel (ULSD) can only be insufficiently separated with the classic separation systems. To solve this problem, a membrane process with different organic/inorganic membranes for the selective separation of water droplets from ULSD and an innovative water‐in‐oil online sensor were developed.     

Al2O3和SiC微滤膜的疏水改性及其油固分离性能研究

以正辛基三乙氧基硅烷和乙醇分别作为改性剂和溶剂,采用接枝聚合法对平均孔径为500 nm的Al₂O₃膜和SiC膜进行疏水改性,考察了改性剂浓度、改性液温度和改性时间对膜表面疏水效果的影响,并对比了疏水改性前后两种陶瓷膜的表面性质及疏水改性后的油固分离性能,进行了反冲实验和稳定性测试。结果表明,两种陶瓷膜材料在改性剂浓度为0.2 mol·L^-1,改性液温度为40℃,改性时间为12 h时,疏水改性效果最好,得到的疏水Al₂O₃膜和SiC膜的水接触角分别为134°±1°和140°±1°,经改性后的SiC膜的疏水效果优于Al₂O₃膜。在油固分离实验中,疏水Al₂O₃膜和SiC膜均对固体炭黑有良好的截留性能,但疏水改性对SiC膜的油品通量提升更为显著,两种膜的稳态通量分别为1134 L·m^-2·h^-1和1408 L·m^-2·h^-1。反冲操作对疏水SiC膜的通量恢复更有利。     

面向油水分离的无机膜制备及应用进展

膜技术是处理含油污水及含水油液的有效分离方法。无机膜材料由于可调变的表面性质和良好的稳定性,即使在苛刻的条件下,在分离油水方面表现出优异的分离性能。本文首先阐述了设计与制备油水分离膜的理论基础,包括分离过程中压力驱动力和膜表面特性对膜通量和选择性的影响;然后综述了当前国内外用于油水分离的无机膜的制备及其应用进展,重点介绍分子筛膜、金属氧化物/金属氢氧化物膜和氧化石墨烯膜等的研究,分析了在不同油水混合物中研究者们调控无机膜表面性能的策略,提出膜表面润湿性和膜结构是提高膜分离效率和抗污染性的关键;最后指出抵制含大量表面活性剂、碱液及有机聚合物种的乳化油对膜造成污染,是无机膜亟需解决的问题,并展望了无机膜在分离油水方面的发展方向。     

Poly(vinylidene fluoride) fibrous membranes doped with polyamide 6 for highly efficient separation of a stable oil/water emulsion

Ideal membranes toward separation of stable oil/water emulsions should have surface hydrophilicity and submicron pores in the separating layer. However, electrospun membranes made from poly(vinylidene fluoride) (PVDF) cannot meet these requirements, failing to remove oil droplets from a stable oil/water emulsion. By doping with a certain polyamide 6 solution, surface hydrophilicity, and interconnected pores with submicron size are successfully achieved. As a result, separation of a stable emulsion with an efficiency above 99% is exhibited by the modified PVDF membranes. Moreover, underwater oleophobicity of the modified PVDF membranes imparts them with good antifouling performance. The modified PVDF membranes could have great potentials in practical stable oil/water emulsion separation. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 44980.     

超亲水/水下超疏油膜的制备及油水分离性能

工业生产和频繁的溢油事故产生大量的含油废水,其高效分离依然面临全球性的挑战。具有仿生浸润特性的膜可以选择性透过水或油,分离效率高且操作简单而广泛应用于油水分离。本文通过一步浸渍法将TiO₂纳米颗粒和聚乙烯吡咯烷酮（PVP）原位固化到不锈钢网上制备了具有微/纳米层级结构的超亲水/水下超疏油油水分离膜。重点考察了TiO₂/PVP涂覆液浓度（质量分数1%、3%、5%、7%、9%）对膜的浸润特性和油水分离性能的影响。实验结果表明,不同TiO₂/PVP浓度改性的膜具有超亲水/水下超疏油特性,水的接触角均为0°,在水中油的接触角达160°,油水分离效率大于99.5%。膜通量随浓度的增大先减小后增加,当质量分数为3%时膜通量最大为8422.5L/（m²·h）。经过30次连续油水分离后,其分离效率仍大于99.5%,表明TiO₂/PVP-SS （stainless steel）膜有良好的耐久性和稳定性。因此,TiO₂/PVP-SS仿生特殊浸润膜材料在油水分离领域具有经济、高效、环境友好的潜在优势。     

超亲水SiO2修饰膜的构建及其油水乳液分离性能

采用硅溶胶和多巴胺作为修饰剂,通过一步反应在微孔聚丙烯膜(MPPM)表面构建了SiO₂修饰层。利用FTIR、ESEM和EDX对膜进行了表征,发现膜表面SiO₂颗粒分布非常均匀。水/油接触角及纯水通量实验结果表明,修饰膜具有超亲水性及水下超疏油性,透水能力强,水通量大[在0.1 MPa时,水通量高达(5100±500)L·m^-2·h^-1]。油水乳液分离结果表明,修饰膜能有效分离油水乳液,在0.05 MPa时,油水乳液水通量达2830 L·m^-2·h^-1,油截留率达99.8%以上,即使过膜压力增大到0.15 MPa,油截留率也能保持在99%以上,且膜表面的油污可用水清洗除去,展现出很好的应用前景。     

Electrospun nanofibrous polyvinylidene fluoride-co-hexafluoropropylene membranes for oil–water separation

Effective separation of oil from water is of significant importance globally for various applications such as wastewater treatment, oil spill cleanup, and oil purification. Among the numerous approaches for oil removal, membrane separation is considered one of the most promising approaches due to its selectivity and ease of operation. Electrospinning is a promising technique for producing polymeric membranes with tunable structures with interconnected pores, large surface area, and high porosity. In this study, hydrophobic poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-HFP) nanofibrous membranes were electrospun and used for this purpose. The effects of various parameters (e.g., polymer concentration, applied voltage, tip to collector distance, and feed rate) were investigated to find the optimum electrospinning conditions. Further, the electrospun membranes were characterized according to average fiber diameter, morphology, average pore size, and wettability to identify the combinations most likely to succeed in oil–water filtration. The physical–chemical properties of the membranes (i.e., thickness, areal density, porosity, average pore size, water/oil contact angle, hydrostatic pressure head, and oil filtration flux) were studied based on standard test methods. The separation efficiency of eight electrospun membranes with various pore sizes and average fiber diameters were tested for diesel/water mixtures. A linear relation was found between the initial oil flux and the average pore size of the membranes. The maximum oil filtration flux of about 224 L/m²/h, achieving over 75% oil recovery in 10 min, was obtained for the electrospun membrane with the average pore size of 4.5 μm. The membranes were successfully used for eight consecutive oil–water separation cycles without noticeable loss of flux.