紧实型GO/PVDF复合膜对有机染料的去除性能研究

Study on removal characteristics of organic dyes by tight GO/PVDF composite membranes

采用氧化石墨烯(GO)改性PVDF膜,利用浸没沉淀相转化的方法制备了紧实型GO/PVDF复合膜,对膜的亲水性、纯水通量和表面Zeta电位等性能进行了考察,并选择罗丹明B和甲基橙分别代表正负电荷染料,对膜的吸附、脱附和截留性能进行了考察。结果显示,膜的纯水通量从45.10 L/(m^2 · h)增加到58.40 L/(m^2 · h)。GO含量为0.50%(质量)时(M2),膜的综合性能较优。GO/PVDF复合膜对罗丹明B的吸附效果较好,1.5 d之后,M0~M3的吸附量分别为1.02、1.24、1.79和1.49 mg/g。乙醇对罗丹明B的脱色率达到80%以上。膜对甲基橙的吸附效果较差,M2的吸附量仅为0.46 mg/g,0.10 mol/L HCl溶液对甲基橙脱色率达到86%以上。膜对两种染料的截留率均保持在57.60%和57.20%以上。为纳米材料改性有机膜的制备以及对有机染料的去除提供了一定的科学依据。

The PVDF membrane was modified by graphene oxide (GO), and the compacted GO/PVDF composite membrane was prepared by immersion precipitation phase transformation. The hydrophilicity, pure water flux and surface zeta potential of the membrane were investigated. Rhodamine B and methyl orange were selected as positive and negative charge dyes to investigate the adsorption, desorption and retention properties of membranes. The results showed that the pure water flux of membrane increased from 45.10 L/(m^2 ·h) to 58.40 L/(m^2 ·h). When the content of GO was 0.50%(mass)(M2), the comprehensive performance of membrane was better. GO / PVDF composite membranes had a good adsorption effect on Rhodamine B. After 1.5 d, the adsorption capacity of M0- M3 were 1.02, 1.24, 1.79 and 1.49 mg/g respectively. The decolorization rate of Rhodamine B by ethanol was over 80%. The adsorption capacity of M2 was only 0.46 mg/g, and decolorization rate of methyl orange by 0.10 mol/L HCl solution was over 86%. The retention rates of two dyes remained above 57.60% and 57.20%. This study provided a scientific basis for the preparation of nano-materials modified membranes and their characteristics of organic dye removal.