Patent ID: 9687792
Date: 2017-06-27
CPC Classifications: B01D

Claim:
1. A process for preparing a thin film composite membrane, comprising: (a) preparing an aqueous phase comprising a polyamine and an organic phase comprising a polyfunctional acid halide, wherein the aqueous phase or organic phase or both include an additive comprising: (b) applying the aqueous phase to a surface of a porous support membrane to form a coated support membrane; and (c) applying the organic phase to the coated support membrane and interfacially polymerizing the polyamine and the polyfunctional acid halide to form a discrimination layer of a thin film composite membrane comprising the porous support membrane and the discrimination layer, the thin film composite membrane having a boron rejection that is greater than the boron rejection of a thin film composite membrane prepared in the absence of the boron rejection-enhancing additive.