维生素B_6的热分解过程和非等温热分解动力学研究

Studies on the Non-isothermal Decomposition Kinetics of Vitamin B_6

目的 :研究维生素B6的热分解过程及机理。方法 :应用热重法研究维生素B6在 30 70 0℃的热分解。结果 :维生素B6的热分解分二步。第一步在脱HCl的同时伴随有分子间脱H2 O ,其动力学方程为 :dα/dt=A·e-E/RT·1/ 2 (1 α) 3,表观活化能E =32 5 .2 7kJ/mol,指前因子A =7.2 2× 10 32 /s。结论 :维生素B6的热稳定性较好 ,在 173℃～ 2

AIM The purpose is to study the non isothermal decomposition process and mechanics of vitamin B 6. METHOD\ The TG technique was used to observe between 30~700℃. RESULTS The decomposition of vitamin B 6 was performed by two stages. Vitamin B 6 loses HCl at the first stage together with losing H\-2O. The kinetic equation obtained was \%dα/dt=A·e -E/RT ·1/2(1 α) 3\%; activation energy obtained was 325.27 kJ/mol; and preexponential factor A obtained was 7.22×10 32 /s as well. CONCLUSION\ Vitamin B 6 is rather thermal stable, and it loses HCl together with losing H 2O at temperature range of 173℃～271℃.