PERFORMANCE OF POROUS CELLULOSE ACETATE MEMBRANES DURING EXTENDED CONTINUOUS OPERATION UNDER PRESSURE IN REVERSE OSMOSIS PROCESS USING AQUEOUS SOLUTIONS

The experimental separation and product rate data obtained in the extended continuous test runs for the systems glycerol-water and sodium chloride-water show that the solute transport parameter, (DAm/K), remains unchanged as the pure water permeability constant, A, decreases because of membrane compaction during continuous service under pressure. This observation establishes an experimental basis, and offers an analytical means of predicting solute separation as the product rate decreases because of membrane compaction during continuous operation of the reverse osmosis process. This prediction technique is illustrated for the systems glycerol-water, and sodium chloride-water using a few typical films. © 1968, American Chemical Society. All rights reserved.