Study on the Purification of Bischofite Brine and Preparation of Lightly Burned Magnesium Oxide
In order to efficiently utilize the natural crystalline bischofite produced after potassium extraction from Qinghai Salt Lake,this paper proposes a new method for purifying bischofite and preparing light burned magnesium oxide.The high-purity bischofites were obtained by the dissolution-precipitation method to separating the impurities of potassium chloride and sodium chloride from magnesium chloride solution using the solubility differences of magnesium chloride,potassium chloride,and sodium chloride in anhy-drous ethanol in this study.And then,the high-purity light burned magnesium oxide was prepared by direct decomposition method using purified salt lake brine as raw material.The results showed that a purity of 99.82%bischofite(MgCl2·6H2O)could be obtained by separating the potassium chloride and sodium chlo-ride impurities from magnesium chloride solution of the salt lake through the dissolution-precipitation method,and the high-purity magnesium oxide with a purity of 99.50%was obtained by decomposing the bischofite.The research results are of great significance for the efficient resource utilization of the natural crystalline bischofite produced after potassium extraction from Qinghai Salt Lake.