Patent ID: 9662615
Date: 2017-05-30
CPC Classifications: B01D

Claim:
1. A method for making a composite polyamide membrane comprising a porous support and a thin film polyamide layer, wherein the method comprises the step of applying a polyfunctional amine monomer and polyfunctional acyl halide monomer to a surface of the porous support and interfacially polymerizing the monomers to form a thin film polyamide layer, wherein the step of applying the polyfunctional acyl halide monomer to the porous support comprises the step of combining the polyfunctional acyl halide monomer with a non-polar solvent at a concentration of 0.18 to 4 weight percent to form a coating solution which is applied to the surface of the porous support, and wherein the interfacial polymerization is conducted in the presence of a phosphate compound which is provided in a molar ratio of at least 1:1 with the polyfunctional acyl halide monomer, wherein the phosphate compound is represented by Formula (I): wherein R wherein the interfacial polymerization is characterized by consuming at least 80 mg of the polyfunctional acyl halide monomer per square meter of polyamide membrane, and wherein polyfunctional amine monomer comprises m-phenylene diamine and the polyfunctional acyl halide comprises trimesoyl chloride.