Caustic magnesite - preparation and properties

The paper presents the selected results of the thermal decomposition of natural magnesite for preparation of active MgO. At the temperature of selective decomposition of magnesite intermediate phases exhibiting enhanced reactivity and low mechanical stability are formed. Evolution of carbon dioxide is accompanied by decrepitation of active magnesia. The selective decomposition and the accompanying decrepitation of the solid may be conveniently used as a way of enriching the chemically active magnesia by simple screening. Magnesia is accumulated in the undersize fraction, whereas undecomposed calcium carbonate and silica remain in the oversize fractions.