Removal of alcohols, amines, and aliphatic acids in aqueous solution by NS‐100 membrane

Abstract

Abstract Removal of alcohols, amines, and aliphatic acids in single‐solute aqueous solution in the concentration range from 0.001 to 0.01 M have been studied using the NS‐100 membrane. All the tests were conducted at 600 psig, 25°C, and a flow rate of 0.30 gpm. The mechanism of solute separation by the NS‐100 membrane differs from that of the cellulose acetate membrane. There was no significant correlation between the removal and the hydrogen bonding ability of the organic solute. Instead, for a given organic solute, its removal increases with the increases in the degree of crosslinkage of the skin layer of NS‐100 membrane, and is proportional to its degree of ionization (or degree of dissociation). For organic compounds having a same functional group, the removal of a compound increases with the increase in molecular weight and/or molecular branching. All of these are attributable to the relative nonpolarity and the anion exchanger characteristics of the membrane as well as to the steric resistance for the solute to permeate through the membrane.