The simultaneous removal of calcium and chloride ions from calcium chloride solution using magnesium-aluminum oxide

We investigated the removal of Ca2+ and Cl from CaCl2 solution at 20-60°C, using magnesium-aluminum oxide, Mg0.80Al0.20O1.10, prepared by the thermal decomposition of a hydrotalcite-like compound, Mg0.80Al0.20(OH)2(CO3)0.10· 0.78H2O. The degree of Ca2+ and Cl removal from the solution increased with increasing initial CaCl2 concentration, temperature, and quantity of Mg0.80Al0.20O1.10 added. When Mg0.80Al0.20O1.10 was added to 0.25 M CaCl2 solution in a Mg0.80Al0.20O1.10/CaCl2 molar ratio of 20, the degree of Ca2+ and Cl removal from the solution at 60°C after 0.5 h was 93.0% and 98.2%, respectively. These results reveal that Mg0.80Al0.20O1.10 has the capacity to remove Ca2+ and Cl simultaneously from aqueous solution.