Synthesis of oxidized chlorine compounds by electrodialysis using a strongly basic anion exchange resin

The work investigated processes for treating solutions similar in composition to concentrates obtained from reverse-osmosis desalination of water containing sodium chloride, using the method of electrodialysis.Two-chamber electrolyzers equipped with MA-41 anion membranes were used to electrolyze model solutions.Sodium chloride solutions were placed in the anode chamber, while the cathode chamber was filled with an alkaline solution at a concentration of 200 mg-eq/dm 3 .Electrolysis processes were conducted at anodic current densities ranging from 1.67 to 8.33 A/dm.It was found that the intensity of chloride oxidation increased with higher anodic current density and higher chloride concentrations in solutions.Alongside the formation of active chlorine, other oxidized chlorine compounds were also formed, as indicated by the discrepancy between the number of oxidized chlorides and the synthesized oxidized chlorine compounds at the initial electrolysis stage.Extended electrolysis periods did not achieve high concentrations of oxidized chlorine compounds in the anolyte due to significant losses via degassing in the form of Cl 2 and ClO 2 .A significant increase in the current efficiency of active chlorine compounds was achieved by introducing the strongly basic anion exchange resin AB-17-8 into the anode chamber, which effectively adsorbed hypochlorite anions and other oxidized chlorine anions.The yield of adsorbed ClO, ClO 2 -and ClO 3 -anions decreased due to degassing processes involving Cl 2 and ClO 2 .