Thermal Decomposition of Phosphate Ore by Using Differential Scanning Calorimetric Method

Abstract

Phosphate ore was decomposed by using thermogravimetric (TG) and differential scanning calorimetric (DSC). The TG-DSC curves contained different sizes and heating rates. The results showed that phosphate ore had four weight loss stages at the range of 40 ~ 1100°C. With the particle size decreasing, the third weight loss stage became more obvious in TG curves and the endothermic peak became sharper in DSC curve ; the starting and ending temperature of thermal decomposition process moved to higher,the weight loss rate also tended to increase; the activation energy of phosphate ore endothermic decomposition process was calculated by Owaza method in 600~800°C, the average activation energy was 202.80 kJ / mol. It provided a basis for the utilizing of phosphate ore.

Thermal Characteristics of Selected Phosphate Ores and the Effect of Inorganic Salts on Their Calcination

“…Obtained results and ranges are in correlation with the findings of various previous researchers. ,− However, most of them assigned the decomposition of organic matter as the only possible explanation for the mass loss during the second step. Although MS curves for m / z = 44 (mostly associated with the CO 2 molecule) show some increase in this range, there are also clear peaks for m / z = 17 and m / z = 18 lines (mainly associated with the H 2 O molecule).…”