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用ＴＧ－ＤＴＡ热分析法研究黄铁矿在不同粒度和不同升温速率及不同气氛中的焙烧过程。随着黄铁矿粒度的减小，焙烧反应的起始温度降低，黄铁矿氧化生成三氧化二铁和四氧化三铁的同时也将形成中间产物硫酸铁和硫酸亚铁；大约在６００℃以上，硫酸铁和亚铁分解为氧化铁和二氧化硫。黄铁矿的粒度相同时，改变升温速率得到的热分析曲线亦不相同，随升温速率的增大其ＤＴＡ曲线放热区间变宽，焙烧过程中不易形成部分中间产物硫酸铁和硫酸亚铁。相同粒度的黄铁矿在相同升温速率，但不同的气氛中焙烧得到的ＴＧ－ＤＴＡ曲线表明，随着氧浓度的升高，黄铁矿的氧化焙烧速度加快，致使物料自身温度升高，则不易生成铁的硫酸盐。
TG-DTA thermal analysis of pyrite in different particle size and heating rate and different atmosphere roasting process. With the reduction of the pyrite size, the initial temperature of the roasting reaction decreases. The oxidation of pyrite to ferric oxide and ferroferric oxide will also form the intermediate ferric sulphate and ferrous sulphate. At about 600 ° C Above, iron sulfate and ferrous oxide are decomposed into iron oxide and sulfur dioxide. When the pyrite particle size is the same, the thermal analysis curve obtained by changing the heating rate is also different. As the heating rate increases, the exothermic range of DTA curve becomes wider, and some intermediate products of ferric sulfate and ferrous sulfate are not easily formed during the calcination. The TG-DTA curve of pyrite with the same particle size at the same heating rate but different atmosphere shows that as the oxygen concentration increases, the oxidation roasting speed of pyrite accelerates, so the temperature of the material itself increases, Not easy to generate iron sulfate.