镍铝合金催化油酸甲酯加氢饱和的热力学和动力学分析

Thermodynamic and kinetics analysis of catalytic hydrogenation of methyl oleate over Ni-Al alloy

采用Benson和Constantinous-Gani基团贡献法及对应状态法估算油酸甲酯和硬脂酸甲酯的热力学基础数据,分析油酸甲酯中C=C加氢饱和的热力学参数。同时,在消除传质影响的条件下测定Ni-Al合金催化油酸甲酯加氢饱和的动力学数据,计算反应的表观活化能并建立了相应的动力学方程。结果表明:油酸甲酯加氢饱和制备硬脂酸甲酯为放热反应;在433~463 K温度区间内,反应的标准摩尔反应焓约为-104.5 kJ/mol,且反应的平衡常数大于10~5;Ni-Al合金在温度433~463 K催化油酸甲酯加氢饱和的反应速率可以表示为r=5.03×10^(-4)e^(-5 236/T)c1.14p1.31,表观活化能为43.53 k J/mol。

Thermodynamic parameter of hydrogenation of the C=C bond in methyl oleate were studied based on the basic thermodynamic data of methyl oleate and methyl stearate estimated by Benson and Constantinous-Gani group contribution methods and corresponding-state method. Kinetics of catalytic hydrogenation of methyl oleate over Ni-Al alloy was also analyzed in the absence of mass-transport limitation,the apparent activation energy was calculated and corresponding kinetic equation was established.The results indicated that hydrogenation of methyl oleate to prepare methyl stearate was an exothermic process,with an standard molar enthalpy of reaction of approximate-104. 5 k J/mol between 433 K and463 K. The equilibrium constant for the hydrogenation of methyl oleate was more than 10~5. The apparent activation energy for the hydrogenation of methyl oleate over Ni-Al alloy was 43. 53 kJ/mol between 433 K and 463 K. A rate equation in the form of r = 5. 03 × 10^（-4）e^（-5 236/T）c1. 14 p1. 31 was finally developed and fitted well with experimental data.