用于VOC回收的PVDMS-Al2O3中空纤维复合膜

摘要

Sorption isotherm of chloroform in polyvinyl dimethylsiloxane (PVDMS) polymer film was measured via the gravimetric method, and this film was confirmed experimentally to be good membrane material to recover chloroform from gas stream with high sorption capacity. A new PVDMS-Al2O3 composite hollow fibre membrane was further prepared by coating a PVDMS film on the outer surface of Al2O3 hollow fibre porpous substrate prepared by a dry/wet phase inversion method. Microstructure of the composite membranes was examined by scanning electron microscopy (SEM), indicating the PVDMS coating layer was uniform, free of defects, and around 15μm thick. Performance of the PVDMS-Al2O3 composite hollow fibre membranes for chloroform recovery was investigated. By comparing the experimental data that derived from a mathematical model, the permeabilities of chloroform and nitrogen in the PVDMS polymer membrane were obtained. The effects of temperature and feed flow rate on the chloroform recovery and permeate concentration were investigated both experimentally and theoretically.