Abstract
This article considers the possibility of processing sodium sulfate (Na2SO4) solutions generated in various industrial processes into valuable products - sulfuric acid (H2SO4) and sodium hydroxide (NaOH) using the electrodialysis method. The problem of processing sodium sulphate solutions is relevant due to their significant volume and high content of inorganic impurities, while traditional methods of purification are energy-intensive and economically inexpedient. The authors have analysed the existing methods of obtaining and processing sodium sulphate solutions by electrodialysis using MC-40, MA-41 and MB-2I membranes and Ralex BM membranes. In purpose of electrodialysis the schemes of 3-chamber and 6-section electrodialyzers using cation- and anion-exchange membranes of MC-40, MA-41 (RF) and EDC1R, EAC1R (PRC) grades were applied. The scheme of bench installation of a multichamber electrodialyzer using EDAM and EDCM membrane brands was considered. The conditions of experiments on 3 installations according to the method of probabilistic-deterministic planning of experiments by Malyshev V.P. The dependences for the first installation were obtained: the degree of conversion on the concentration of Na2SO4, the duration of the process on the cathodic density and the content of MgSO4 impurity. Dependences of energy consumption on concentration of initial solution and current density at 3 installations allow to judge about expediency of electrodialysis process.