Phase relationships in the stabilization of Dolomite

Abstract

Dolomite is a double carbonate of magnesium and calcium, the formula being written as CaCO3.MgCO3. In most massive dolomite occurring in nature, impurities such as silica, alumina, iron oxide and alkalies are present in variable amounts. On Calcination of dolomite, the magnesium carbonate molecules is first broken up with the evolution CO2 followed by the calcite molecules, resulting in the formation of CaO and MgO. These two oxides have a tendency to hydrate, especially if formed at lower temperatures. The Silica present in the dolomite combines with lime to forms calcium ferrites. The alumina present may either form calcium aluminium ferrite or calcium aluminates.