Composite membrane for sepn. of water from aq. amine solns. - has sepn. layer of polyvinyl alcohol post-crosslinked by acid in vapour phase

摘要

The composite membrane (I) has (1) sepn. layer of crosslinked polyvinyl alcohol (II) which has been post-crosslinked by acids which act on (II) layer via vapour phase; (2) porous support layer (III); and (3) reinforcing or carrier layer (IV). (III) and (IV) comprise amine-resistant material. The process claimed involves removing water from aq. amine solns. by pervaporation, where amine soln. to be dewatered is contacted with a face of (I) while chemical potential of water on other side of (I) is kept at value lower than that of chemical potential of water on the one side. Mixt. to be dewatered is partic. liq. mixt. of vapours, partic. satd.. ADVANTAGE - (I) has high sensitivity and cross-membrane flow, and long term resistance to hot amine solns..