Abstract:

By using the microcalorimetry techniques, thermogravimetric analysis and LC-MS, the mechanism of the thermal degradation of aconitine, hydrolysis mechanism and the heat change of aconitine in the soil environment was explored, and the half-life of aconitine was determinated (t_1/2=0.973 h). While, aconitine is unstable and easily degradable in air, also easy to hydrolyze in alkaline solution. The thermal decomposition of aconitine in air displays three stages. The temperature range in the three stages, respectively, is 185-213℃, 248-468℃, 484-579℃. The corresponding reaction order is n=1/4, n=4, n=2 in the three stages; the activation energy in the three stages is 154.53 kJ·mol^-1, 100.97 kJ·mol^-1, 120.08 kJ·mol^-1. Aconitine should be stored as far as possible in the low temperature, dry and isolated air environment.

Key words: aconitine, hydrolysis, pyrolysis, half-life, microthermal technology, thermodynamics

摘要：

采用微量热技术及热重法，结合液质联用技术，探讨了乌头碱的热降解机理、水解机理的热效应等，求出乌头碱的半衰期。结果表明，乌头碱在空气氛围中不稳定，碱性溶液中易水解t_1/2=0.973 h。空气环境中热分解分3步，其分解温度区间分别为185～213℃，248～468℃和484～579℃。相应的反应级数分别为n=1/4、n=4、n=2。对应的活化能分别是154.53，100.97和120.08 kJ·mol^-1。乌头碱应尽可能储存于低温干燥并隔绝空气的环境中。

关键词: 乌头碱, 水解, 热解, 半衰期, 微量热技术, 热力学