Composite membrane and method for making the same
AssigneeDow Global Technologies LLC
InventorWilliam E. Mickols
Life of this patent
Estimating the term…
Abstract
A composite membrane and method for making the same, comprising a porous support and a polyamide surface. The subject membrane provides improved flux and/or rejection rates. The subject membrane is further capable of operating at lower operating pressures. The subject method includes reacting a polyfunctional amine with a polyfunctional acyl halide to form a polyamide. The method includes the step of contacting a complexing agent with the polyfunctional acyl halide prior substantial reaction between the polyfunctional acyl halide and a polyfunctional amine. The subject process is easily adapted to commercial scale manufacturing processes and is particularly suited for making nanofiltration and reverse osmosis composite membranes.
Claims9
A composite membrane comprising a polyamide layer fixed upon a porous support wherein the polyamide layer comprises a complexing agent having a solubility parameter of from about 15 to about 26 J1/2 cm−3/2 and has a binding core selected from non-sulfur atoms selected from Groups IIIA-VIB and Periods 3-6 of the conventional IUPAC period table, wherein said binding core remains detectable within the polyamide layer after the membrane has been operated in reverse osmosis mode using pure water feed at a 24 gfd flux rate through the membrane with a permeate recovery between 0.5% to 25% at 25° C. for 24 hours.
Dependencies are inferred from the claim text.