Patent ID: 6723422
Filing Date: 2004-04-20
Classification: B01D,B32B,Y10T

Abstract:
A composite reverse osmosis membrane comprising:a porous support; and a polyamide skin layer formed on the porous support, wherein the composite reverse osmosis membrane is produced by a method comprising the steps of: forming a layer on the porous support by coating a solution A comprising an amino compound having at least two reactive amino groups; contacting the layer with a solution B comprising a polyfunctional acid halide compound; and subsequently contacting the layer with a solution C comprising the polyfunctional acid halide compound at a concentration higher than a concentration of the polyfunctional acid halide compound in the solution B to form the polyamide skin layer; and wherein a contact angle between a surface of the polyamide skin layer and water is no more than 45Â°, sodium chloride rejection is at least 98%, and a permeate flow rate is at least 0.7 m3/m2Â·day when evaluated by using feed water which has pH 6.5, 0.05 weight % of salt, an operation pressure of 5 kgf/cm2 and a temperature of 25Â° C.