LiOH·H_2O在空气中的失水动力学研究

Kinetics of Thermal Decomposition of LiOH·H_2O in Air

用热分析技术热重法、差热分析法及微分热重法(TG-DTA/DTG)研究了Li OH.H2O(氢氧化锂)在空气中的热分解过程。热分析结果表明,Li OH.H2O在空气中分两步分解。用Friedman法、Flynn-Wall-Ozawa(FWO)法和ASTM E698法求取了Li OH.H2O脱水过程的活化能E为85.71 kJ/mol,指前因子以lgA表示,其值为9.81,失水过程拟合的最可几模型为Bna,即自催化的n级反应,动力学模式函数为f(α)=αa(1-α)n。

The thermal decomposition processes taking place in the solid-state LiOH · H2O have been studied in air using TG-DTA/DTG techniques. TG-DTA/DTG curves showed that the decomposition proceeded through two well-defined steps in air. The activation energies of dehydration process were calculated through Friedman, Flynn-Wall-Ozawa（FWO） and ASTM E698 methods, and the possible kinetic modelling and parameters have been estimated through the multiple-linear regression method.