Purification of Underground Water From Heavy Metal Ions with a Composite Nanofiltration Membrane

Abstract

A method for obtaining a composite membrane with a surface layer for water treatment processes is proposed. Nylon-AC composite membranes were obtained by immersion of a polymer substrate made of nylon-66 in a solution of cellulose acetate (AC) in acetone. The properties of membranes have been studied, the parameters of nanofiltration of composite membranes have been established. The content of heavy metal ions in underground water has been studied. The specific performance of membranes for distilled and underground water is determined depending on the number of applied layers of AC. The selectivity of the composite membrane with respect to metal ions was established, the retention capacity for which averaged 86 % with a specific productivity of 137 dm3/(m2·h), which exceeds the performance of a commercial nanofiltration membrane.