石膏脱水热分解动力学研究

Research on the kinetics Thermal Dehydration of Gypsum

采用TG-DSC热分析法对石膏脱水反应过程进行了实验研究,结合热分析的TG曲线,利用普适积分法处理试验结果,通过对不同机理函数的拟合计算分析,判断出石膏脱水的总反应过程是由化学反应机理控制,确定反应级数模型是最佳机理函数,并求得其动力学基本参数:表观活化能=137.879 KJ/mol,指前因子=1.515×1016 S-1,所建立的数学模型预测结果和实验曲线相吻合,其误差最大不超过4.985%。

The dehydration process of gypsum were investigated and discussed by TG-DSC thermal analysis experiment in this paper. According to TG curve, the universal integral method was used to deal with experimental data. The optimal conversion function was determined though fitting calculation and analysis for different mechanisms function. Via calculation we found that the dehydration process of gypsum was dominated by chemical reaction mechanism, the reaction order function was the best model and the basic dynamics parameters was obtained., apparent activation energy = 137. 879 KJ/mol, the pre-exponential factor = 1.515 x 1016 S-l.The result of mathematical model prediction was consistent with experimental data. The maximum error was less than 4.985 %