this invention relates to uses of graphene oxide , and in particular graphene oxide on a porous support , and a membrane comprising these materials . this invention also relates to methods of dehydration , which include vapour phase separation and pervaporation . pervaporation is a method of separating mixtures of liquids using a membrane . pervaporation consists of two basic steps : permeation of the permeate through the membrane and evaporation of the permeate from the other side of the membrane . pervaporation is a mild which can be used to separate components which would not survive the comparatively harsh conditions needed for distillation .