氢气还原重晶石制备硫化钡的热力学研究

Thermodynamic Study on Barium Sulfide preparation by Hydrogen-reduced Barite

通过对氢气还原重晶石制备硫化钡的热力学理论计算和动力学研究,计算了不同温度下反应体系可能发生的反应的标准摩尔焓变、反应物相变化、热重曲线变化,分析了各热力学参数与温度之间的关系,考察了反应温度、反应气氛、原料组成、原料杂质对硫酸钡转化率的影响。研究结果表明:氢气还原重晶石过程是吸热反应,但吸热量不大,充分预热物料,迅速提高反应温度,避免反应物在低温停留时间,有利于提高硫化钡生成率;使用氢气还原可以降低体系的O_(2)含量,提高硫化钡生产率;原料中杂质会降低产物BaS含量;氢气还原是重晶石在700℃开始失重,855℃失重速度达到最快。

Through the thermodynamic calculation and dynamics of barium sulfide preparation by hydrogen-reduced barite research, the standard molar enthalpy changes, reactant phase changes, thermogravimetric curve changes of possible reactions at different temperatures were calculated, the relationship between the thermodynamic parameters and temperature was analyzed, the effects of reaction temperature, reaction atmosphere, composition of raw material and impurities in raw material on barium sulfate conversion rate were investigated. The study showed that the hydrogen-reduced barite is an endothermic reaction, but the heat absorption is small, the formation rate of barium sulfide can be increased by fully preheated the material, rapidly increased the reaction temperature and avoided the reactants staying at low temperatures for long. Technology of hydrogen-reduced barite can reduce the O_(2)content in the system and increase the productivity of barium sulfide. Impurities in raw material can reduce the BaS content of product. Hydrogen-reduced barite begins to lose weight at 700 ℃ and reaches the highest weight loss rate at 855 ℃.