有机物极性对超滤膜过滤性能的影响

为研究有机物极性对超滤膜过滤性能的影响,用超滤膜过滤有机物含量相当,有机物极性成分不同的5种水样,基于滤饼堵塞过滤模型和中间堵塞过滤模型对试验结果拟合。研究表明,超滤膜对不同极性有机物去除率由高到低为:VHA>SHA>NEU>CHA,在膜的浓水、正冲水、反洗水及化学清洗废液中,疏水性有机物的比例也相对较高。疏水性有机物浓度由高到低的水样1、水样2、水样3、水样4和水样5,过滤结束时通量分别为起始通量的91%,80%,69%,56%和45%,滤饼层过滤阻力系数kp和膜孔吸附系数kc均随水样中疏水性有机物含量的升高而增大,说明疏水性有机物在膜表面沉积和在膜孔的吸附性能都比亲水性有机物强,疏水性有机物是造成超滤膜有机污染的主要因素。

Effect of Organic Polarity on Ultrafiltration Membrane Filtration Performance

Deionized water was applied to prepare 5 kinds of water samples, in which the organics were equivalent in contents, but different in polar components. Ultrafiltration membrane was used to filter the samples. Based on the filter cake and intermediate blocking filtration models, the effect of organic polarity on membrane filtration performance was analyzed. The results showed that the removal rate of organic matters with different polarities was VHA>SHA>NEU>CHA. At the end of filtration, compared with initial fluxes, the fluxes of sample 1, sample 2, sample 3, sample 4 and sample 5 were 91%, 80%, 69%, 56% and 45%, respectively. The cake layer filtration resistance coefficient denoted by kp and membrane pore adsorption coefficient denoted by kc were increased with the elevation of hydrophobic organic contents, indicating that both the deposition of hydrophobic organics on membrane surface and the membrane pore adsorption performance were stronger than hydrophilic organics. Hydrophobic organic matters were the major factors causing the organic pollution of ultrafiltration membrane.