头孢硫脒热分解动力学研究

采用TG-DTG(thermal gravity -differential thermal gravity)法研究了头孢硫脒的热分解过程动力学。头孢硫脒热分解为一步完成，开始失重时的温度为430~450 K。运用Flynn-Wall-Ozawa法、Kissinger-Akahira-Sunose法和Starink法计算了头孢硫脒热分解过程中的活化能值，发现活化能均随着热分解转化率的升高而降低。通过Málek 法得到头孢硫脒晶体的热分解动力学三因子分别为E_α=109 kJ/mol、ln A=30.60 s^-1、最概然动力学模型为SB(0.241 7, 0.658 9)。预测头孢硫脒在273.15 K以下时的理论贮存期为3年。

Kinetics of the thermal decomposition of cefathiamidine

The kinetics of the thermal decomposition of cefathiamidine was investigated by thermal gravity-differential thermal gravity (TG-DTG). The thermal decomposition of cefathiamidine was accomplished in one step, and the initial decomposition temperature ranged from 430 K to 450 K. The activation energy of the thermal decomposition process of cefathiamidine was obtained using the Flynn-Wall-Ozawa method, Kissinger-Akahira-Sunose method, and Starink method. The activation energy decreased with an increase in the thermal decomposition conversion rate. Further, the three factors of the thermal decomposition kinetics of the ceftiamidine crystals were obtained using the Málek method. The calculated E_α was 109 kJ/mol, lnA was 30.60 s^-1, and most probable kinetic model was SB(0.241 7, 0.658 9). The calculated theoretical shelf time of cefathiamidine was three years below 273.15 K.