Lg Nanoh2o, Inc.

Lg Chem, Ltd

Lg Baboh2o, Inc.

Chongkyu Shin

Keunwon Song

Jeff Koehler

Alexis Foster

Young Ju Lee

Evgueni Rozenbaoum

Youngju Lee

Young Hoon Ko

Provided is a post-formation process for preparation of a highly permeable thin film composite membranes for reverse osmosis, particularly for use with brackish water at low energy conditions. The process includes contacting a polyamide discrimination layer of a TFC membrane with a solution containing an oxidizing agent to form a treated membrane, followed by contacting the treated membrane with a solution containing a reducing agent. The resulting membrane exhibits enhanced water flux while maintaining salt rejection. Also provided are reverse osmosis membranes prepared in accord with the method, and modules containing the highly permeable thin film composite membranes, and methods of purifying water using the membranes or modules.

Methods of enhancing water flux of a TFC membrane using oxidizing and reducing agents

Provided is an interfacial polymerization process for preparation of a thin film composite membrane, which can be used for nanofiltration, forward osmosis, or reverse osmosis, particularly for use with brackish water or seawater. The process includes contacting a porous support membrane with an aqueous phase containing a polyamine to form a coated support membrane, and applying an organic phase containing a polyfunctional acyl halide to the coated support membrane to interfacially polymerize the polyamine and the polyfunctional acyl halide to form a discrimination layer of a thin film composite membrane, where during formation of the membrane, the polyfunctional acyl halide is purified in situ by removal of hydrolyzed acyl halide through addition of a salt rejection-enhancing additive that includes a biguanide compound, dicarbonate compound, pentathiodicarbonate compound, or salt thereof. Also provided are the membranes prepared by the methods and reverse osmosis modules containing the membranes.

Additives for salt rejection enhancement of a membrane

Provided is an interfacial polymerization process for preparation of a highly permeable thin film composite membrane, which can be used for nanofiltration, forward osmosis, or reverse osmosis, particularly for use with brackish water at low energy conditions. The process includes contacting a porous support membrane with an aqueous phase containing a polyamine and a flux enhancing combination of additives that includes a metal chelate additive containing a bidentate ligand and a metal atom or metal ion and a phosphoramide to form a coated support membrane, and applying an organic phase containing a polyfunctional acid halide to the coated support membrane to interfacially polymerize the polyamine and the polyfunctional acid halide to form a discrimination layer of the thin film composite membrane. Also provided are the membranes prepared by the methods and reverse osmosis modules containing the membranes.

Chemical additives for enhancement of water flux of a membrane

Provided is an interfacial polymerization process for preparation of a highly permeable thin film composite membrane, which can be used for nanofiltration, or forward or reverse osmosis, for use with tap water, seawater and brackish water, particularly for use with brackish water at low energy conditions. The process includes contacting a porous support membrane with an aqueous phase containing a polyamine and a flux enhancing combination, which includes a metal chelate additive containing a bidentate ligand and a metal atom or metal ion and a dialkyl sulfoxide, to form a coated support membrane, and applying an organic phase containing a polyfunctional acid halide to the coated support membrane to interfacially polymerize the polyamine and the polyfunctional acid halide to form a discrimination layer of the thin film composite membrane. Also provided are the membranes prepared by the methods and reverse osmosis modules containing the membranes.

Growing community of inventors

Rancho Palos Verdes, CA, United States of America

Chongkyu Shin