应用热分析技术研究菱镁石矿轻烧过程动力学

Application of Thermal Analysis Technique to the Decomposition Kinetics of Magnesite

以辽宁大石桥晶质菱镁石矿为原料,采用TG、DSC热分析技术研究菱镁石粉末分解动力学。实验研究表明,菱镁石在500～700℃发生分解,失重率为43.13%。由TG曲线得出菱镁石分解反应表现活化能E=172.32kJ/mol,反应级数n=0.78;DSC曲线表明反应活化能E=199.44kJ/mol,反应级数n=0.87。TG、DSC曲线研究结果有较好的一致性,表明热分析技术在菱镁石分解动力学中可以得到良好的应用。

The decomposition kinetic of crystalloid magnesite of Liaoning Da Shi-qiao is studied by TG and DSC methods. The experiment shows that the decomposition temperature of magnesite is 500-700℃, the mass loss ratio is 43. 13%. The activition energy E of the decomposition reaction is 172. 32kJ/mol, the reaction order n is 0. 78 by the analysis of TG curve. And E is 199. 44kJ/mol,n is 0. 87 by the analysis of DSC curve. The consistent results obtained from two methods show that the thermal analysis technique can be applied in the decomposition kinetics of magnesite.