物质的分离,一般采用过滤、蒸馏、重结晶、萃取、离心及吸附等方法。近30年来,随着膜学研究的飞速发展,利用选择性透过分离膜进行气体或液体分离的研究,取得了令人瞠目的成果。1960年美国加州大学的罗伯(S.Loeb)及索里拉金(S.Sourirajan)用醋酸纤维素制备出内部呈多孔结构、表层为0.1微米厚的致密结构的非对称膜,从而诞生了具有广泛实用意义的反渗透法,成为分离膜 Material separation, the general use of filtration, distillation, recrystallization, extraction, centrifugation and adsorption and other methods. In the recent 30 years, with the rapid development of membrane research, the use of selective separation through the membrane for gas or liquid separation research, and achieved remarkable results. In 1960, S.Loeb and S.Sourirajan of the University of California, U.S.A. prepared a dense structure of asymmetric membrane with a porous structure and a surface layer of 0.1 micron thick with cellulose acetate, Broad practical significance of reverse osmosis, a separation membrane