应用于膜蒸馏过程的F26微孔膜的初步研究

以N-甲基吡咯酮作为溶剂 ,丙酮为溶胀剂 ,聚乙二醇 4 0 0为添加剂利用相转换法制备出偏氟乙烯 六氟丙烯共聚物 (F2 6 )的疏水微孔膜并且应用在膜蒸馏过程中 .研究了丙酮以及N 甲基吡咯酮 丙酮体系对膜参数以及结构的影响 .通过SEM观察了膜的微观结构 ,发现用N 甲基吡咯酮 丙酮体系制得的微孔膜兼具指状孔和海绵状孔结构 .无添加剂条件下制得的F2 6膜其对蒸馏水的接触角比相同条件下制备的PVDF膜大 .在用相转换法制备的F2 6和PVDF的疏水膜中 ,选择具有适当孔径结构的微孔膜用于膜蒸馏实验 ,F2 6膜的膜蒸馏系数比PVDF膜来得大 ,相同操作条件下的膜蒸馏通量也比PVDF膜高 .

PRELIMINARY STUDIES ON F26 MICROPOROUS MEMBRANES IN MEMBRANE DISTILLATION

Poly(vinylidene fluoride-co-hexafluoro propylene)(F26)-based asymmetry micro-porous membrane has been fabricated by a phase inversion process and applied in membrane distillation.Acetone (sweller),N-methyl pyrrolidone (solvent) and polyethylene glycol 400 (additive) were used in casting solutions.Different effect of acetone and N-methyl pyrrolidone/acetone on membrane structure parameters was investigated and demonstrated by SEM.F26 microporous membrane with fingerlike and sponge structure was prepared in N-methyl pyrrolidone/acetone.F26 membrane prepared without any additives is superior to PVDF membrane by making a comparison of their contact angle to distilled water.The membrane distillation coefficient of the experimental F26 membrane is higher than that of the experimental PVDF membrane,which can be ascribed to the special membrane structure of F26.Membrane distillation flux of F26 membranes was a little higher than that of the PVDF ones under the same operational conditions.