Patent ID: 7445712
Filing Date: 2008-11-04
Classification: B01D

Abstract:
1. An asymmetric forward osmosis membrane having three layers comprising: (a) a skin layer made from polymeric material having a top surface as a rejection surface of the asymmetric forward osmosis membrane, and a bottom surface, wherein the density of the skin layer is greater than 50% polymer by volume, and wherein the skin layer has an average thickness of from about 8 to about 18 microns; (b) a porous scaffold layer having a first surface bonded to the bottom surface of the skin layer and a second surface, wherein the scaffold layer is made from the same polymeric material as the skin layer and wherein the density of the scaffold layer is from about 15% to about 30% by volume, and wherein the scaffold layer has an average thickness of from about 25 to about 75 microns; and (c) a hydrophilic support fabric.