Effects of Additives on the Reductive Decomposition of Phosphogypsum in the CO Atmosphere

The effect of the reaction time and the amount of additives on the decomposition rate and temperature of phosphogypsum were studied in the weak reducing atmosphere of 3%Vol CO by using the mixture of phosphogyp-sum and a certain percentage of CaCl2, Fe2O3 and MgO additives. The result shows that the decomposition rate of phosphogypsum reached 85% by adding CaCl2 and Fe2O3, and the decomposition temperature of phosphogypsum was only 950°C which was 100 °C lower than the one of decomposition reaction of phosphogypsum without any adductives. And the addition of MgO had no significant effects on the decomposition of phosphogypsum under the same condition.