Continuous dialysis of hydrochloric acid and lithium chloride: permeability of anion-exchange membrane to chloride ions

Abstract

A counter-current two-compartment dialyzer equipped with an anion-exchange membrane Neosepta-AFN was used to study dialysis of a hydrochloric acid and lithium chloride mixture. To quantify this process, several characteristics were calculated from the data obtained at steady state. First, the dialysis process was characterized by the acid recovery yield and rejection coefficient of salt, which were in the range of 61–98% and 62–94%, respectively (for HCl and LiCl concentrations from 0.1 to 1.0 kmol m−3 and volumetric liquid flow rates from 8 × 10−9 to 24 × 10−9 m3 s−1). Furthermore, this study proved that dialysis of an HCl + LiCl mixture can be quantified by a single characteristic, i.e., the permeability coefficient of the membrane to chloride ions, which is a function of the concentration of both the components in the feed.