Preparation of high pure refractory grade magnesium oxide from east coast sea water

Abstract

Preparation of good quality magnesium oxide from seawater is the most challenging job because the vast majority of undesired impurities come from seawater during the precipitation stage. Hence, the double salt route has been developed as a very unique technique to prepare refractory grade magnesium oxide from seawater. Controlled addition of carrier reagent at the precipitating stage precipitates magnesium as double salt. The double salt is transformed to magnesium carbonate (MgCO₃), which after calcination forms magnesium oxide (MgO). The product quality has been established by elemental analysis, PXRD, FTIR, TG/DTG, and FESEM. Commercially available MgCO₃ and MgO of HiMedia have also been characterized simultaneously for comparison. The prepared magnesium oxide shows very high purity of 99.75%, which is shown from EDS measurement and PXRD and can be suitable as basic refractory material for industrial purposes.