During its manufacturing, borax chemical factories have to get rid of boric magnesium slag, which could be purified into magnesium sulfate heptahydrate if well used. Boric magnesium slag mainly contains MgCO3 and also contains other impurities as MgO, SiO2, Fe2O3, FeO, CaO, Al2O3, MnO, etc. [Read More]