The intrinsic kinetics of catalytic hydrogenation of rosin to abietenoic-acid and abietanoec-acid on Pt/C catalyst was investigated by using a FYX-2G high-pressure agitated autoclave. The effects of internal and external diffusion were eliminated by adopting measures of reducing granularity of catalyst, adding No.200 solvent oil and raising rotational speed of the agitator. During the experiments, the changes of reactant concentrations and product concentrations with reaction time were traced on-line at the temperature range of 403 K to 433 K and under the pressure range of 3.0 MPa to 7.0 MPa. Based on the experimental data and with the help of EVIEWS software, a suitable reaction mechanism for the hydrogenation of abietic-acid in the rosin was selected from 17 probable reaction mechanism models. The result shows that the catalytic hydrogenation of abietic-acid to abietenoic-acid and to abietanoec-acid consists of two parallel reactions; and the most possible reaction mechanism is that the main component abietic-acid in rosin is not absorbed, and for the catalytic hydrogenation reaction of the abietic-acid with the adsorbed hydrogen, the absorption of atomic hydrogen on the catalyst surface could be the controlling step. It was also found that the activated energies for the formation of abietenoic-acid and abietanoec-acid are 27.758 kJ.mol-1 and 237.12 kJ.mol-l, respectively.%采用FYX-2G型高压搅拌釜,以Pd/C为催化剂进行松香催化加氢制备二氢和四氢枞酸本征动力学的研究.通过减小催化剂粒度、加入200号溶剂油和增加高压釜的搅拌转速,消除了加氢过程内外扩散的影响,在温度403～433K、压力3.0～7.0 MPa下,在线跟踪了反应物和产物的浓度随时间的变化关系,采集动力学数据,使用EVIEWS软件对17种可能的反应机理模型进行筛选,结果表明,枞酸加氢生成二氢枞酸和四氢枞酸是并行反应;最可几的反应机理为:松香中的主要成分枞酸分子不吸附,枞酸分子与催化剂表面上被吸附的氢原子进行反应,氢原子的吸附为控制步骤,生成二氢枞酸和四氢枞酸的活化能分别为27.758 kJ·mol-1和237.12 kJ·mol-1.
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