3,5-二硝基水杨酸铈的制备、热分解机理及非等温反应动力学

摘要

用3,5-二硝基水杨酸和硝酸铈为原料,制备了3,5-二硝基水杨酸铈(CeDNS),采用元素分析、X射线荧光光谱和FTIR对其进行了表征.用TG和DSC以及变温固相原位反应池/傅立叶变换红外光谱(RS-FTIR)联用技术研究了3.5-二硝基水杨酸铈的热分解机理,对主放热反应的DSC峰进行了数学处理.计算得到了动力学参数和动力学方程.结果表明,3,5-二硝基水杨酸铈的分解反应共有3个阶段,其中包括一个脱水吸热过程和一个主放热过程,主分解反应发生在第2阶段,主分解反应的表观活化能E.与指前因子A分别为:159.17 Kj·mol-1和1011.33s-1,主分解阶段的反应机理服从Avrami-Erofeev方程(n=1/4),主分解反应的动力学方程为:da/dt=1011.33×4(1-α)[-In(1-α)]3/4 e-1.92×104/T.%Cerium 3,5-dinitrosalicylate(CeDNS)was synthesized by using 3,5-dinitrosalicylic acid,sodium hydroxide and cerium nitrate as raw materials,and was characterized by elementary analysis,X·ray fluorescence and FTIRspectraoscopy.The thermal decomposition mechanism and kinetm parameters of the decomposition reaction ofCeDNS were investigated by means of TG/DSC and in situ condensed phase thermolysis/FHR(RS-FTIR).The kineticequation of decomposition reaction was obtained.The results show that the decomposition process of CeDNS hasthree stages and the main exothermie decomposition reaction Occurs in the second process.The kinetic parameters ofthe main exothermie decomposition reaction fire:Ea=159.17 kJ·mol-1,A=1011.33 s-1.The kinetic equation can be expressed as:dα/dt=1011.33×4(1-α)[-1n(1-α)]3/4 e -1.92×104/T.