Pahokee泥炭腐殖酸的相对分子量分布特征及其对菲的吸附影响

使用切面流超滤方法,将Pahokee泥炭中分离出的腐殖酸分为具有不同相对分子质量的8个级分(UF1:<1k;UF2:1～3k;UF3:3～5k;UF4:5～10k;UF5:10～30k;UF6:30～50k;UF7:50～100k:UF8:>300k),表明该泥炭中的腐殖酸主要分布于几个高相对分子量级分中(UF5,UF6和UF8),可占所提取的腐殖酸质量的83 5%.体积排阻色谱的流出曲线说明可以通过超滤手段将腐殖酸这种复杂的、非均匀性的大分子物质分成相对均一的、窄相对分子量分布的分子.而两种方法所测相对分子量的差异可能与两个操作系统间不同的操作条件有关.各超滤级分的腐殖酸对菲的吸附实验说明相对分子量是影响腐殖酸吸附的一个重要参数;随相对分子量的增加,腐殖酸对菲的吸附及其非线性特征均增强.     

离子筛与醋酸纤维素混合超滤膜的制备及降氟性能

在超滤膜制备过程中，间铸膜液中引入了亲氟物质－水合氧化镧，经熟化制备的混合超滤膜具有分离大分子和降低水体中氟离子浓度两种功能，以含氟饮用水为研究对象，对其混合膜的降氟机理进行了探讨。     

超滤膜材质对处理电泳漆液的影响

本文研究了聚砜，酞侧基聚砜，磺化聚砜，聚丙烯腈，醋酸纤维素，氰乙基醋酸纤维素，氯甲基化聚砜和季胺化聚砜等材质超滤膜的亲水性能，荷电性能以及它们对超滤阳极和阴极电泳漆液的影响，实验结果表明：亲水性较强，电负性较强的氰乙基醋酸纤维素和醋酸纤维素膜，适合用于处理阳极电泳漆液；而亲水性较强，电中性和电正性较强的氯甲基化聚砜和季胺化聚砜膜，则适合用于处理阴极电泳漆液。     

预处理＋超滤技术处理饮用水

在查阅了大量的国内外文献资料基础上，主要介绍了超滤技术及预处理应用于饮用水净化的研究。尽管超滤是一种去除病原微生物（病原菌、病毒和病原原生动物）有效的消毒工艺，但因它的截留分子量比较高，去除天然有机物相对无效。试验证明，适当的预处理可使超滤膜不仅能去除天然水中大量颗粒状物质，同时也可去除溶解性有机物及THMFP。     

水体溶解有机质富集分离方法的研究进展

溶解有机质,作为全球碳循环的主要组成部分,在水生生态系统的各种物理、化学和生物过程中扮演着非常重要的角色。富集分离溶解有机质是研究其化学特征和环境地球行为的必要前提。在总结XAD树脂分离技术在溶解有机质富集分离的基础上,本文对其它三种常用的分离方法—二乙氨基乙基纤维素(DEAE)吸附分离法、超滤(UF)分离法以及反渗透(RO)分离法进行了综述。介绍了各分离方法的分离原理、分离流程、存在的优缺点及应用范围。最后对超滤或反渗透与XAD树脂相结合的联用技术在溶解有机质环境地球化学研究中的应用前景进行了展望。     

Towards green membranes: preparation of cellulose acetate ultrafiltration membranes using methyl lactate as a biosolvent

Ultrafiltration membranes were prepared using cellulose acetate (CA) as a polymer, LiCl and CaCl₂ as porogens and methyl-(S)-lactate as a solvent. CA, methyl lactate and the porogens used in this work are obtained from renewable resources; they are biodegradable, non-toxic and non-volatile organic compounds. Flat sheet ultrafiltration membranes were prepared by the phase inversion technique. A molecular weight cut-off between 15 and 35 kDa (polyethylene glycol) and pure water permeability between 13 and 177 litres h^? 1m^? 2 bar^? 1 were obtained. These parameters are in the ideal range for water treatment industry. Improvement of pollutant degree and ecotoxicity of the process was evaluated by ‘green’ metrics by the P (pollutants, persistent and bioaccumulative) and E (ecotoxicity) parameters. Both of these variables were recorded as zero using our method. This study represents a step ahead towards the production of ultrafiltration polymeric membranes by a ‘greener’ process than current methods.     

Development of clean technology in alcohol fermentation industry

A zero-discharge system for the alcohol fermentation industry was developed by recycling distillery waste (stillage). Stillage was able to be recycled as cooking water for the next fermentation after treating it with appropriate separation processes. Ultrafiltration with a ceramic membrane played a key role in the separation processes. When the permeate from the ultrafiltration of stillage was recycled to the cooking step, the total fermentation time was prolonged from 60 to 70–80 h, but the average ethanol production yield (8.8%) was similar to that in the conventional process (9.0%). In contrast, direct recycle of stillage without membrane filtration showed negative effects on both fermentation time and alcohol yield as recycling was repeated. This new process was confirmed to have stable operation over eight recycles. This new clean technology for the ethanol production industry makes it possible to eliminate the stillage treatment steps using the conventional biological treatment processes such as anaerobic digestion and activated sludge steps currently being operated in industry.     

超滤-反渗透集成膜技术再生洗浴废水的研究

洗浴废水是轻度污染的废水,具有较高的回用价值。文章采用超滤-反渗透技术,利用超滤作为反渗透的预处理技术,超滤-反渗透集成膜技术回用洗浴废水。讨论了操作条件分别对超滤和反渗透出水的浊度、细菌总数、COD和膜通量的影响。实验证明了超滤-反渗透集成膜技术回用洗浴废水的出水水质浊度小于3度,细菌总数小于100个/mL,COD小于10mg/L,出水水质指标达到了《生活饮用水卫生标准》,可直接进行回用。     

对含油废水处理方法的新探索

含油废水对生态环境造成严重污染。膜分离作为一种能耗低、设备简单、操作方便和分离性能好的技术,在含油废水处理中显示出广阔的应用前景。本文主要介绍了含油废水的特征及其处理方法,分析了微滤、超滤和反渗透等膜分离技术的特点及它们在含油废水中的应用。     

水质环境条件对恒流超滤过程的影响研究

研究了用聚丙烯腈中空纤维超滤膜组件净化含腐殖酸类有机物模拟废水的恒流膜过程,考察了水中的Ca2+浓度、离子强度、pH值等水质环境条件对超滤膜过滤性能的影响。试验结果表明,增加水中Ca2+浓度,增大溶液离子强度,以及降低pH值均能增大跨膜压差的增加速率;增加水中Ca2+浓度和降低pH值的效果较明显。Ca2+、离子强度变化基本不影响有机污染物的去除率,而pH值的升高降低了膜对水中有机污染物的去除率。