PVA/PVP/SiO_(2)复合膜过滤器的制备及油水分离性能

Preparation and Oil-Water Separation Performance of PVA/PVP/SiO_(2) Composite Membrane Filter

以钢丝网为基底,采用浸涂法制备油水分离膜过滤器。首先,将聚乙烯醇(PVA)、聚乙烯吡咯烷酮(PVP)与纳米二氧化硅(SiO_(2))制备聚乙烯醇/聚乙烯吡咯烷酮/二氧化硅(PVA/PVP/SiO_(2))复合材料;再将其浸涂在钢丝网上,置于戊二醛蒸汽中进一步交联,得到超亲水/水下超疏油的PVA/PVP/SiO_(2)复合膜过滤器。利用热失重表征了PVA/PVP/SiO_(2)复合材料的热性能;探究了PVP和SiO_(2)含量对膜过滤器表面润湿性的影响;同时,测试了复合膜过滤器的油水分离效率和重复利用率。结果表明:PVP和纳米SiO_(2)的加入提高了复合膜的热稳定性和水下疏油性,当SiO_(2)、PVP与PVA的质量比为0.5∶0.4∶1,PVA溶液的质量分数为10%时,所制备的PVA/PVP/SiO_(2)复合膜过滤器对油水混合物表现出优异的分离性能,初次油水分离效率最高可达到99.5%,分离通量可达到7 083.41 L/(h·m^(2)),当在重力驱动下重复分离20次后,油水分离效率仍超过97.2%,分离通量在6 927.77 L/(h·m^(2))以上。

A oil-water separation membrane filter was prepared on a stainless steel mesh by a dip-coating method.Firstly,the polyvinylalcohol/polyvinylpyrrolidone/nano silicon dioxide(PVA/PVP/SiO_(2))composite material was prepared with PVA,PVP and nanosilica.Then the PVA/PVP/SiO_(2) composite membrane filter with super hydrophilicity/underwater superoleophobicity was obtained by dip-coating the as-prepared composite on stainless steel mesh and further crosslinking in glutaraldehyde steam.The thermal properties of the composite were characterized by thermogravimetric analysis.The effect of the content of PVP and SiO_(2) on the wettability of the composite membrane filter surface was investigated.The oil/water separation efficiency,and the recyclability of the composite membrane filter were also tested.The results reveal that the addition of PVP and nano silica increases the thermal stability and underwater oleophobicity when the mass ratio of SiO_(2),PVP and PVA is 0.5∶0.4∶1,and the mass fraction of PVA solution is 10%.The PVA/PVP/SiO_(2) composite membrane filter exhibits excellent separation performance for oil-water mixture.The separation efficiency is 99.5%initially,and the flux reaches 7083.41 L/(h·m^(2)).Throughout 20 separation cycles solely driven by gravity,the separation efficiencies are above 97.2%,the fluxes are above 6927.77 L/(h·m^(2)).