Abstract: A membrane comprising a pore-free separation layer, wherein the separation layer consists of poly-dimethyl aminoethyl methacrylate homopolymers or N-vinylpyrrolidone dimethyl aminoethyl methacrylate copolymer or N-vinylcaprolactam dimethyl aminoethyl methacrylate copolymer or N-vinylcaprolactam N-vinylpyrrolidone dimethyl aminoethyl methacrylate terpolymers.

Abstract: A method for removing C.sub.1 -C.sub.3 alkanols from their mixtures with hydrocarbons or heteroatom-containing hydrocarbons wherein the method comprises utilizing a membrane comprising a non-porous separation layer of cellulose ester containing polymeric materials, characterized in that said polymeric material is a polymer blend of a first polymer selected from cellulose esters and at least one second polymer selected from polyvinyl pyrrolidone (PVP), copolymers of vinyl pyrrolidone and vinyl acetate (VP-co-VA), polyethylene glycol (PEG), N,N,-dialkylated polyacrylic amide (DPAA) and cellulose esters other than said first polymer.

Abstract: Process for the manufacture of composite plasma membranes with the production of a pore-free impermeable polymer layer on a porous substrate through the plasma polymerization of a gaseous mixture, said gaseous mixture containing a hydrocarbon as the matrix-forming component and a nitrogen-, silicon-, sulphur- or phosphorus-containing inorganic compound as the non-matrix-forming component and an oxygen-containing compound, by means of glow discharge in an electrical alternating field. The pore-free impermeable polymer layer is produced directly on a porous substrate without the use of an impermeable intermediate layer, said porous substrate having a pore diameter of less than 100 nm on the side facing the pore-free polymer layer. The composite plasma membranes are used for separating C.sub.1 -C.sub.3 alkanols from mixtures thereof with other organic liquids using the method of pervaporation.

Abstract: In a process for removing water by pervaporation or vapor permeation from mixtures with alcohols and/or carboxylic acids and/or carboxylic esters by bringing the mixture into contact with one side of a membrane and removing the water-containing permeate in vapor form from the other side of the membrane, the membrane used has been obtained by plasma polymerization.