Study on Scale-up of Electro-Electrodialysis [EED] Cell for HI Concentration

An experimental study on scale-up of Electro-electrodialysis(EED) to increase the efficiency of HI decomposition section in the IS(Iodine-Sulfur) process was carried out. The EED stack extends the effective area of the membrane to 20 times of that formerly used in a single EED unit cell. The experiment was carried out using HIx solution() at and various solution flow rates of 20, 30, 40 and 50 cc/min. The increased HI molality in catholyte after one-pass throughout from the EED stack was 3 mol/kg-, 2.2 mol/kg-, 2 mol/kg- and 1.37 mol/kg- at 20, 30, 40 and 50 cc/min, respectively. These values satisfied the target of HI molality(the increase of HI molality: 2 mol/kg-) in the IS process for hydrogen production of 20 L/hr.