单宁酸-多巴胺涂覆制备染料分离用纳滤膜

通过单宁酸及聚多巴胺涂覆,制备了单宁酸(TA)-聚偏氟乙烯(PVDF)纳滤膜,同时评价了改性膜对刚果红、伊文思蓝、活性嫩黄等染料的分离性能。结果表明,改性后膜表面粗糙度略微增大,亲水性明显增强。同时,改性膜具有水下超疏油的性质,能够完全抵抗水下油污的污染。2wt% TA-PVDF纳滤膜对多种染料的截留率能达到96.5%以上,且对刚果红、伊文思蓝、活性嫩黄等染料的截留通量都超过65.7 L/(m2?h?bar)。另外,改性膜在染料分离时截留通量基本不变,稳定性较强,在工业染料废水处理方面有一定的应用前景。     

纳滤膜分离技术在废水处理中的应用

纳滤作为一种新型分离技术，在处理废水的同时能够回收有用物质，因而在废水处理中得到了越来越广泛的应用。首先简介了纳滤膜分离技术的原理及特点，然后论述了纳滤膜的分离机理，接着介绍了用于表述膜的结构与性能之间关系的空间电荷、固定电荷和细孔等数学模型，最后对纳滤膜在生活污水、石油工业废水、化学工业废水、食品工业废水、造纸废水、印染废水、酸洗废液、重金属废水和电厂二次废水处理中的应用作了较全面的综述。     

氯化聚氯乙烯复合纳滤膜的制备及其在模拟RB5染料废水处理中的应用

以氯化聚氯乙烯（CPVC）超滤膜为基膜,采用单宁酸（TA）和哌嗪（PIP）在CPVC膜表面共沉积后与交联剂均苯三甲酰氯（TMC）进行界面聚合得到PA/TA/CPVC复合纳滤膜,采用扫描电镜（SEM）、原子力显微镜（AFM）、红外光谱及接触角对PA/TA/CPVC复合纳滤膜进行了表征,并探讨了干燥时间、TA/PIP浓度比、TA+PIP总浓度、TMC浓度对PA/TA/CPVC复合纳滤膜微观结构与性能的影响。结果表明,TA/PIP浓度比最佳为7/3,TA/PIP层的最佳干燥时间为20min,PA/TA/CPVC复合纳滤膜的纯水通量随着TA+PIP总浓度的增加和TMC浓度的增加而减少,对PEG1000的截留率均在90%以上。PA/TA/CPVC复合纳滤膜纯水通量最大值为4.5L/(m² · h · bar),此时PEG1000的截留率达到95.8%。对模拟RB5染料废水的最大通量为4.3L/(m² · h · bar),此时RB5的截留率为95.4%,对模拟RB5染料废水的稳定性较好。     

Preparation and performance of novel thermal stable composite nanofiltration membrane

The novel thermal stable composite nanofiltration membranes were prepared through the interfacial polymerization of piperazine and trimesoyl chloride on the poly (phthalazinone ether) ultrafiltration substrate. The effects of polymerization and testing conditions on membrane performance were studied. The surface morphologies of the substrate and the composite membranes were observed by means of scanning electron microscopy (SEM) and atomic force microscopy (AFM). The separation properties of membranes for dyes and salts were tested. The composite membranes show good thermal stability. The rejection for Na2SO4 was kept over 96%, while the flux reached 400 L·m⁻²·h⁻¹ when it was tested at 1.0 MPa and 80°C. When tested at 1.0 MPa and 60°C, the rejection of the composite membrane for dyes was kept at high level, and the flux reached 180–210 L·m⁻²·h⁻¹, while the rejection for NaCl was lower than 20%. __________ Translated from the Journal of Functional Materials, 2007, 38(12): 2025–2027, 2031 [译自: 功能材料]     

用于喷墨印花染料纯化的自组装GO/TiO2复合纳滤膜的制备

数码喷墨打印技术对墨水高纯度和低含盐量要求,不断促使染料纯化技术的开发与研究。基于氧化石墨烯(GO)/纳米二氧化钛(TiO₂)自组装的纳滤膜材料的开发,探究了纳米TiO₂颗粒尺寸和与GO共混比例,所获最优GO/TiO₂复合纳滤膜中TiO₂颗粒尺寸为60 nm,与GO共混比例为1∶1。其纯水通量为10.69 L/(m²·h·bar),对NaCl和Na₂SO₄的截留分别为12.6%和15.7%,对铬黑T、刚果红和考马斯亮蓝R的截留均高于99%。采用自制的连续恒容渗滤装置对粗品墨水进行染料脱盐浓缩的实验,所获染料的浓度由最初的2.0 g/L浓缩至9.74 g/L,NaCl和Na₂SO₄浓度则由起始10 g/L分别下降至5.3 mg/L和11 mg/L,满足数码印花对墨水高纯度以及低盐度的要求。     

新型复合纳滤膜研究进展

纳滤膜因操作压力低、通量高、具有分离选择性以及运行成本较低等优势引起越来越多的关注,目前已在苦咸水脱盐、污水治理和海水淡化等领域发挥着重要作用。界面聚合作为常见的制备聚酰胺纳滤膜的方法,其聚合反应进程的调控可以有效地调节纳滤膜的微观结构,进而对其分离性能产生重要影响。本文从复合纳滤膜的结构入手,总结了当前常用的提升纳滤膜性能的改性方法,包括优化分离选择层、构建中间层、调整底膜结构三个方面,讨论了界面聚合过程反应单体、添加剂种类、制备条件等对分离层结构和分离性能的影响,并分析了底膜的孔径、孔隙率、亲疏水性等理化性质对复合膜性能的影响以及不同类型中间层的优缺点。在此基础上,总结了当前业界内亟待解决的问题,并对纳滤膜的未来发展趋势进行了展望。     

具有PDA-UiO-66中间层耐溶剂复合纳滤膜的制备及性能

将多巴胺和Ui O-66纳米颗粒共沉积在经1,6-己二胺交联的聚醚酰亚胺（PEI）基膜上构建了纳米复合中间层（PDA-UiO-66），并在中间层上进行界面聚合反应制备了耐溶剂复合纳滤膜（TFN-U）。通过FTIR、XRD、SEM、AFM、水接触角测量仪对膜结构进行了表征和测试，探究了Ui O-66质量浓度对TFN-U膜耐溶剂性、耐污染性以及运行稳定性的影响。结果表明，PDA-Ui O-66纳米复合中间层的引入能提高TFN-U膜的渗透通量，当Ui O-66纳米颗粒质量浓度为0.2 g/L时，TFN-U2膜水通量为63.83 L/(m2·h)，甲醇通量为28.50L/(m2·h)，对刚果红水溶液和刚果红甲醇溶液的截留率为98.2%和93.2%，经无水乙醇、丙酮、乙酸乙酯、正己烷及N,N-二甲基甲酰胺（DMF）浸泡48h后，其对刚果红的截留率均>94%，通量恢复率达到78.1%，在连续24 h过滤刚果红甲醇溶液后，该膜的甲醇通量为14.13L/(m2·h)，截留率为98.3%，表明TFN-U2膜具有良好的耐溶剂性、耐污染性以及一定的运行稳定性。     

新型还原氧化石墨烯/氮化碳复合纳滤膜制备及其性能

高性能石墨烯基复合膜的制备是目前国际研究热点,但是石墨烯基纳滤膜在脱盐中水通量较低,限制其在脱盐中的应用。采用聚多巴胺(PDA)改性聚砜(PSF)膜为基膜,将还原氧化石墨烯(rGO)和超薄氮化碳(uCN)纳米片通过真空抽滤法在基膜表面自组装制备新型还原氧化石墨烯/氮化碳复合纳滤膜。通过场发射扫描电子显微镜、透射电子显微镜、X 射线衍射仪、傅里叶变换红外光谱仪和X射线光电子能谱仪等研究uCN添加对膜结构和形貌的影响,并考察不同uCN添加比例、rGO用量及压力复合纳滤膜性能变化规律。结果显示当在100 mg·L^-1的rGO中添加uCN为20 mg·L^-1时所制备的rGO/uCN复合纳滤膜不仅保持良好盐离子截留率(对Na₂SO₄截留率85.86%,对NaCl截留率30.17%),且水渗透系数是rGO膜的2.15倍(88.50 L·m^-2·h^-1·MPa^-1)。     

荷负电手性壳聚糖纳复合滤膜的制备与性能研究

以聚砜超滤膜作为基膜,以壳聚糖和壳聚糖衍生物的混合物为功能层制备纳滤膜。P2-5复合纳滤（NF）膜对Na2SO4的截留率为93%,相应的通量501.3 L/（m2·h）。电荷效应对NaCl几乎没有影响,而对Na2SO4影响显著。该膜为典型的荷负电膜,适合分离高价阴离子。     

ZrO2-TiO2复合纳滤膜在模拟放射性废水中的应用

核工业、核研究及医疗等过程会产生大量的放射性废水,会对环境和生物体造成严重伤害,必须经过合适的处理后才能排放。采用高性能陶瓷纳滤膜处理模拟放射性废水,考察了跨膜压差、pH和离子浓度等操作参数对Co²⁺和Sr²⁺截留性能的影响,并对操作参数进行了优化。所用陶瓷纳滤膜材料为ZrO₂-TiO₂复合材料,截留分子量为500,纯水渗透率为270 L·m^-2·h^-1·MPa^-1。研究表明,陶瓷纳滤膜对Co²⁺和Sr²⁺两种离子的截留率随着跨膜压差的升高而增大,膜的渗透通量随着跨膜压差的增大呈线性增加。pH变化时,截留率在一定pH范围内先降低后升高,在等电点（pH=7）附近达到最小值;pH=3的情况下,两种离子的截留率均达到最高,Co²⁺和Sr²⁺的截留率均在99%以上,而纳滤膜渗透通量保持稳定。离子截留率和渗透通量均随进料浓度的增大而减小,在2000 min的连续循环操作过程中,陶瓷纳滤膜材料的渗透通量及其对Co²⁺和Sr²⁺的截留率均维持在较高水平。陶瓷纳滤膜在放射性废水处理方面展现出了良好的应用前景。     

新型纳滤膜回收含镍废水的工业研究

介绍了新型纳滤膜处理高浓度电镀工业含镍废水的应用研究.在操作压力2.2 MPa,进料流量1 800 L/h的条件下,纳滤过程可将镍封漂洗水浓缩至20 000 mg/L以上,平均膜通量大于40 L/(h·m2);Ni2+、有机添加剂及硼酸的平均截留率分别大于99%、90%和35%,微孔剂则被完全截留.60 d工业运行结果表明,浓缩液和透过液分别回用于光亮镍电镀槽及镍封漂洗槽,满足电镀生产要求;单批次操作后用清水循环5 min以及运行5 d后用2%柠檬酸溶液循环30 min,能够有效解决膜面污染问题,达到工业化生产的要求,具有显著的社会效益与经济效应.     

Preparation and separation properties of polyamide nanofiltration membrane

Utilizing an interfacial polymerization technique for the preparation of a polymeric composite nanofiltration membrane, both high permeation flux of water and high salt rejection can be achieved. Synthesis conditions, such as concentration of monomer, reaction time, and swelling agent, significantly affected the separation performance of composite membranes. The composite polyamide membrane had a permeation rate of ～2–5 gallon/ft²/day (gfd) and a salt rejection rate of ～94–99% when 2000 ppm aqueous salt solution was fed at 200 psi and 25°C. Also, a higher performance nanofiltration membrane could be prepared by suitably swelling the support matrix in the period of polymerization. The results of various feed concentrations showed that permeate flux decreased with increasing salt concentration in the feed solution. This result may be due to concentration polarization on the surface of polyamide membranes. The separation performance of polyamide membranes showed an almost independent relationship with operation pressure until it was up to 200 psi. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 1112–1118, 2002     

Direct filtration of Procion dye bath wastewaters by nanofiltration membranes: flux and removal characteristics

The treatment and reuse of industrial wastewaters by membrane processes has become more attractive in the last few years due to constraints on water usage. The aim of this study was to investigate the direct filtration of reactive dye house wastewaters by nanofiltration membranes based on permeate flux, and sodium chloride and colour removal. Experiments were performed using both synthetic and industrial dye bath wastewaters with the fluxes of the industrial dye bath wastewaters lower than those of the synthetic solutions. The effects of operating conditions such as pressure and pH were assessed. Studies with DS5 DK type (polysulfone–polyamide) membranes showed that nanofiltration membranes are suitable for direct treatment of wastewaters and the permeate quality was appropriate for reuse in the dyeing process. Pre‐treatment and neutralisation were important for recovery of large amounts of salt and water from the permeate stream. Neutralisation of the solution with HCl rather than H₂SO₄ gave a better permeate from the point of view of the reuse. The highest permeate flux and colour removal and the lowest salt removal were achieved with the HCl neutralisation. Copyright © 2003 Society of Chemical Industry     

纳滤膜的分离机理及其在染料废水处理中应用

根据纳滤膜分离不同性质的物料，评述了纳滤膜分离机理研究进展。纳滤膜分离非电解质时描述模型有立体阻碍-细孔模型；分离电解质和离子时包括空间电荷模型、固定电荷模型、静电阻碍模型和道南-细孔模型。综述了纳滤膜应用于染料废水处理的现状。     

TMC/TMPIP纳滤超薄复合膜的制备

基于哌嗪(PIP)与均苯三甲酰氯(TMC)界面聚合制备纳滤膜的原理,设计并合成了具有支化结构的三亚胺功能基团水相单体--均苯三甲酰哌嗪(TMPIP)盐酸盐,并与TMC界面聚合制得分子结构与TMC/PIP相同的TMC/TMPIP超薄纳滤复合膜。采用傅里叶红外光谱(FTIR)和扫描电镜(SEM)表征了复合膜皮层的化学结构和表面形貌,结果表明在聚砜底膜表面形成了膜厚为100 nm左右的TMC/TMPIP超薄皮层。通过与TMC/PIP复合膜对PEG 200水溶液的分离性能相比较发现,TMC/TMPIP复合膜因其高度的网络化结构和超薄皮层,因而具有更高的截留率和水通量。考察了TMC/TMPIP复合膜对水中不同盐的截留性能,其截留率顺序与TMC/PIP复合膜相同,而通量和截留率均优于后者。     

界面聚合法PI/PP耐溶剂复合纳滤膜的制备与表征

以丙烯酰胺接枝的聚丙烯(PP)超滤膜为支撑层,间苯二胺(MPD)、均苯四甲酰氯(BTAC)分别为水相及有机相功能单体,通过界面聚合及其后续的酰亚胺化制备了聚酰亚胺(PI)/PP耐溶剂复合纳滤膜。讨论了水相浓度、有机相浓度及酰亚胺化溶液配方等条件对复合膜结构及其分离性能的影响。分别采用傅里叶红外光谱仪(FTIR)、扫描电子显微镜(SEM)表征分离层的化学组成及复合膜的形态结构,得到膜的分离、透过及其耐溶剂性能。结果表明,有机相浓度的影响最为显著,支撑膜表面形成了均匀致密的PI分离层,复合膜呈负电性,并具备优秀的耐溶剂性能。实验范围内,MPD、BTAC的浓度分别为8、2 g·L-1,酰亚胺化溶液乙酸酐∶三乙胺∶苯体积比为1∶1∶10时,所制备膜的分离性能较佳,对Na2SO4、酸性艳蓝6B的截留率分别达93.8%和96.9%。     

Separation performance of thin-film composite nanofiltration membrane through interfacial polymerization using different amine monomers

Four kinds of thin-film composite (TFC) membranes were prepared via interfacial polymerization using diethylenetriamine (DETA), triethylenetetramine (TETA), tetraethylenepentamine (TEPA) and piperazidine (PIP) as water-soluble monomer, and trimesoyl chloride (TMC) as organic-soluble monomer. The surface chemical features of the resultant membranes were confirmed by contact angle measurement and Fourier transform infrared spectroscopy (FTIR). The membrane morphology and surface charges were investigated through Scanning electronic microscopy (SEM) and Zeta potential, respectively. Salt rejection was used to evaluate the separation performance of the four kinds of TFC membranes. The results showed that all the four kinds of TFC membranes exhibited typical negatively charged nanofiltration membrane characteristics. The salt rejections followed the sequence: Na₂SO₄ > MgSO₄ > MgCl₂ and the rejection of Na₂SO₄ was all over 80%. It was also found that the solubility of water-soluble monomer in organic solvent played an important role in manipulating the membrane structure, charge properties and thus the separation performance.     

Effect of adding a smart potassium ion-responsive copolymer into polysulfone support membrane on the performance of thin-film composite nanofiltration membrane

Thin-film composite (TFC) nanofiltration (NF) membranes were fabricated via the interfacial polymerization of piperazine (PIP) and 1,3,5-benzenetricart)oiiyl trichloride on polysulfone (PSf) support membranes blended with K^+-responsive poly(N-isopropylacryamideco- acryloylamidobenzo-15-crown-5)(P(NIPAM-co- AAB15C5)). Membranes were characterized by attenuated total reflection Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, atomic force microscope, scanning electron microscope, contact angle, and filtration tests. The results showed that:(1) Under K^+-free conditions, the blended P(NIPAM-co-AAB15C5)/PSf supports had porous and hydrophilic surfaces, thereby producing NF membranes with smooth surfaces and low MgSO4 rejections;(2) With K^+ in the PIP solution, the surface roughness and water permeability of the resultant NF membrane were increased due to the K^+-induced transition of low-content P(NIPAM-co-AAB15C5) from hydrophilic to hydrophobic;(3) After a curing treatment at 95℃, the improved NF membrane achieved an even higher pure water permeability of 10.97 L·m^-2·h^-1 - bar1 under 200 psi. Overall, this study provides a novel method to improve the performance of NF membranes and helps understand the influence of supports on TFC membranes.     

纳滤技术在矿冶领域的应用研究进展

纳滤具有传统处理方法不具备的低能耗、高截留率、较好选择性等优点,可望在国民经济各个领域得到广泛应用。介绍了纳滤技术在矿井水、矿山浸出液、矿山废水以及铅锌、钼、钨等冶炼废水处理中的情况。肯定了纳滤技术的应用效果,指出了现行纳滤技术在实际应用中可能存在的问题、不足与解决方法,同时展望了纳滤技术发展趋势。     

复合式膜生物反应器废水处理技术研究进展

复合式膜生物反应器结合了传统膜生物反应器与接触氧化工艺的优点,能在维持稳定高效的有机物去除率前提下,有效减缓膜污染,减少剩余污泥的排放,并为同步脱氮过程提供良好环境,因此近几年逐渐成为研究热点。文章综述了其构成、工作原理、类型及在处理不同废水中的应用,并展望了今后研究的努力方向。