Sulfuric acid concentration with an electro-electrodialysis process

Laboratoire de Physico-Chimie des Systèmes Polyphasés, C.N.R.S., U.A. 330, B.P. 5051, Route de Mende, 34033 Montpellier France; T. Cohen; Laboratoire de Physico-Chimie des Biopolymères, U.M. 27, C.N.R.S. 2-8 rue Henry Dunant, 94320 Thiais France; P. Dagard; Framatome, Tour Fiat, Place de la Coupole, 92084 Paris la Défense France; L. Albert; Minemet Recherche, 1 Place Albert Einstein, 78191 Trappes France
Hydrometallurgy 01/1988; DOI: 10.1016/0304-386X(88)90004-7

ABSTRACT Commercial anion-exchange membranes exhibit a strong proton leakage which makes them unsuitable for use in the recovery of sulphuric acid from sulphate containing solutions resulting from some hydrometallurgy processes. Experiments are reported which compare membrane permeabilities under electro-electrodialysis conditions. With most commercial membranes, the permeability to sulphate ions decreases rapidly when the acid concentration increases in the anolyte. The highest sulphuric acid concentration is obtained with a prototype membrane which will be shortly produced on an industrial scale.

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