硫酸氢铵分解动力学及其分解机理的研究

INVESTIGATION OF THE KINETICS AND MECHANISM OF DECOMPOSITION OF AMMONIUM HYDROGEN SULFATE

为了筛选适合的化学贮能系统,Wentworth等人曾提出了十项筛选标准。照此标准衡量,硫酸氢铵的分解-合成反应是一个十分理想的贮能系统: NH_4HSO_4(l)?NH_3(g)+H_2(g)+SO_3(g)Prengle也曾就此反应应用于太阳能电站贮能系统的可行性作过理论上的探讨.但是,有关该反应的基础研究进行的还很不够,特别有关分解动力学和分解机理的研究文献尚未见报导。本文用等温热重法和程序升温热重法对硫酸氢铵的热分解动力学进行了研究,并确定了分解机理,为贮能系统的实际应用提供了基础数据。

The thermal decomposition of NH_4HSO_4 was studied by means of thermogravi-metry both at cosntant temperature and linearly increasing of temperature.Three-stageidentification of the function depending on a mechanism was suggested. The experi-mental results and theoretical analysis showed that the thermal decomposition ofNH_4HSO_4 is an one dimensional phase boundary reaction.Kinetic paramters:E=141. 25kJ·mol^(-1), A=1. 563×10^(10)min^(-1) (isothermal run)E=131. 83kJ·mol^(-1), A=3. 3113×10~9min^(-1)(dynamic run)Kinetic compensition effect:lgA=0. 0899E-2. 5143