Manufacturing Process of Activated Magnesia from Bittern and Dolomite

摘要

The manufacturing process of activated magnesia from Bittern (MgCl{sub}2·6H{sub}2O) and dolomite, including dolomite calcinations, sintered dolomite assimilation and halogenations with bittern, was researched in the paper. Dolomite was assimilated in calcium chloride solution and halogenated in hot bittern after calcined at 850～950°C. When the mole ratio of bittern to theory value is about 2.5 times, the high content of activated magnesia was gotten. During assimilations and halogenations process, the concentration of bittern solution about 1.36mol/1 was prone to gain high content (more than 75%) of activated magnesia. The calcined dolomite was easily transformed to magnesium hydroxide at higher temperature such as 60°C, 90°C than low temperature such as 40°C in halogenations step. The content of activated magnesia was higher at 90°C than 60°C in halogenations process. The content of activated magnesia obtained with this technology is 75%-82%.