COMPOSITE SEMIPERMEABLE MEMBRANE, PROCESS FOR PRODUCING THE SAME, AND METHOD OF PURIFYING WATER WITH THE SAME

摘要

The present invention relates to a composite semipermeable membrane which is characterized in that it is a composite semipermeable membrane in which there is formed by polycondensation on top of a microporous support membrane a crosslinked polyamide ultra-thin membrane layer from polyfunctional amine, polyfunctional acid halide and polyfunctional acid anhydride halide, and the flow of water permeate at an operating pressure of 0.3 MPa, a temperature of 25 DEG C and a pH of 6.5 lies in the range from 0.8 to 4.0 m<3>/m<2>.day and, furthermore, the percentage humic acid removal is at least 98%; a method for the production thereof; and a water purification method employing same. With the composite semipermeable membrane obtained by means of the present invention it is possible, in particular, to recover drinking water at a high rate by permitting passage of silica and preventing deposition thereof at the membrane surface while selectively separating/removing the pollutants and trace quantities of harmful materials and their precursors, etc, contained in the raw water in water treatment plants.