The kinetics of the aqueous-phase, stereoretentive hydrogenation of alanine to alaninol over 5 wt % Ru/C catalyst in a three-phase stirred batch reactor is presented. Alanine readily undergoes hydrogenation when in the carboxylic acid form (−COOH), a condition that can be achieved by acidifying the reaction solution with phosphoric acid. The conversion rate is not limited by mass-transport resistances over the ranges of temperature (353−398 K), hydrogen pressure (1.7−13.8 MPa), alanine feed concentration (0.22−0.46 M), and phosphoric acid concentration (0−1.2M) investigated. A Langmuir−Hinshelwood (L−H) kinetic model is presented in which protonated alanine and undissociated phosphoric acid compete for one set of surface sites and H₂ dissociatively adsorbs on a second type of site. The average error between the experimental and predicted conversions over all data collected was 8%.

中文翻译：

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l-丙氨酸水相加氢为l-丙氨酸的动力学

提出了在三相搅拌间歇反应器中在5wt％Ru / C催化剂上丙氨酸向丙氨酸的水相立体保持氢化的动力学。当丙氨酸呈羧酸形式（-COOH）时，很容易进行氢化，这可以通过用磷酸酸化反应溶液来实现。转化率不受温度（353-398 K），氢压力（1.7-13.8 MPa），丙氨酸进料浓度（0.22-0.46 M）和磷酸浓度（0-1.2）范围内的传质阻力的限制M）已调查。提出了Langmuir-Hinshelwood（L-H）动力学模型，其中质子化的丙氨酸和未解离的磷酸竞争一组表面位点和H ₂解离地吸附在第二种类型的位点上。在所有收集的数据中，实验转化率与预测转化率之间的平均误差为8％。