氧化石墨烯复合膜的制备及其在水体中脱除染料的性能

Preparation of GO composite membrane and its performance in removing dyes from water

为同时提高氧化石墨烯(GO)膜的稳定性及分离性能,以戊二醛为交联剂,引入聚乙烯醇(PVA)和二氧化钛(TiO_(2)),采用真空辅助过滤法制备了TiO_(2)/GO/PVA复合膜,通过SEM、TEM、FTIR、XRD对复合膜的形态结构进行表征,并通过接触角仪、错流装置和超声实验测试膜对染料的分离性能及稳定性。结果表明:随着TiO_(2)添加量的增大,TiO_(2)/GO/PVA复合膜的层间距从0.68 nm增加到0.78 nm,水接触角由53.2°降低为48.0°;在错流过滤条件下,TiO_(2)质量分数为2%的TiO_(2)/GO/PVA复合膜分离性能最优,且在长时间连续运行过程中表现稳定,对苋菜红和甲基蓝的截留率保持在99.4%以上,通量最高可达12.14 L/(m^(2)·h·bar)(1 bar=0.1 MPa),且该复合膜具有良好的结构稳定性。

In order to improve the stability and separation performance of graphene oxide(GO)membranes,glutaraldehyde was used as a cross-linking agent,polyvinyl alcohol(PVA)and titanium dioxide(TiO_(2))were introduced,and TiO_(2)/GO/PVA composite membrane was prepared by vacuum-assisted filtration.The morphology and structure of the composite membrane were characterized by SEM,TEM,FTIR,XRD.The dye separation performance and stability of the composite membrane were tested by contact angle meter,cross-flow device and ultrasonic experiment.The experimental results showed that the interlayer distance of the TiO_(2)/GO/PVA composite membranes increased from 0.68 nm to 0.78 nm,and the water contact angle decreased from 53.2°to 48.0°with the amount of TiO_(2) added increased.Under the cross-flow filtration conditions,TiO_(2)/GO/PVA composite membrane with 2%(mass fraction)TiO_(2) had the best and stable separation performance during the long-term continuous operation.The rejection rate of TiO_(2)/GO/PVA composite membrane for Amaranth and Methyl Blue remained above 99.4%,and the maximum flux can reach 12.14 L/(m^(2)·h·bar)(1 bar=0.1 MPa).In addition,this composite membrane had good structural stability.