Formation process of magnesium carbonate and control of magnesium oxide content

The lightly burned magnesium oxide powder obtained by calcination of magnesia ore was used as raw material, and the magnesium sulfate solution was obtained by acid dissolution, and the basic magnesium carbonate products were prepared by ammonium bicarbonate precipitation method, and the products with different molecular structures were obtained under different pyrolysis conditions, and it was determined that the molecular formula of the products obtained at 60-90°C could be expressed as Mg5(CO3)4(OH)2-8H2O, while the molecular formula of the products obtained by pyrolysis above 95°C was Mg5(CO3)4(OH)2-4H2O.

In this study, the content of magnesium oxide was controlled by adding a certain amount of ammonia during the precipitation process, and the amount of magnesium oxide obtained by pyrolysis at 60℃ was 43.5%, and the precipitation rate of zhanzhou of magnesium sulfate solution was above 88%. The surface morphology of the products was observed by SEM.