Patent ID: 6440309
Filing Date: 2002-08-27
Classification: B01D

Abstract:
A pervaporation membrane consisting essentially of a porous ceramic support of pore size 500 angstroms or less containing surface hydroxyls or having been hydrolyzed to create surface hydroxyls and having been treated to contain surface water in the amount equivalent of 2-24 monolayers of water, said surface having vinyl loweralkoxy silane or vinythydroxy silane chemically attached to the external surface and/or pore surface in an amount of at least 10 micromoles of said vinyl loweralkoxy silane or vinyl hydroxysilane per square meter of said ceramic membrane, said surface activated ceramic support having graft polymerized onto the vinyl alkoxysilane or vinyl hydroxysilane a water insoluble or water soluble vinyl monomer, by free-radical graft polymerization, resulting in terminally and covalently bonded vinyl polymer in an amount of at least 2 milligram of said vinyl polymer per square meter of said ceramic membrane support surface.