反应精馏合成丙酸丙酯模拟与动力学

Simulation and Reaction Kinetics of Synthesis of Propyl Propionate by Reactive Distillation

采用反应动力学研究装置,以强酸性离子交换树脂Amberlyst46^(TM)为催化剂,研究正丙醇和丙酸合成丙酸丙酯的反应动力学。在消除了内外扩散的情况下,考察了催化剂用量、醇/酸摩尔比、反应温度和搅拌转速对丙酸转化率的影响。在催化剂用量15g、醇/酸摩尔比1.2、反应温度80℃、搅拌转速400r/min的较优操作条件下,确定了反应动力学参数,获得动力学数据反应活化能E_a=40.35kJ/mol,指前因子k_0=2.16×10~3 L/(mol·min),并运用于稳态模拟中,考察了进料温度以及各段塔板数对产物纯度的影响。优化后的操作条件为进料温度70℃、精馏段塔板数2、反应段板数21、提馏段塔板数11,此时丙酸丙酯产品的摩尔分数达到99.88%以上。

The reaction kinetics of n-propyl propionate synthesis from n-propyl alcohol （ProOH） and propionic acid （ProAc） was studied by using strongly acidic ion-exchange resin Amberlyst46TM as catalyst in the reaction kinetics apparatus. The influences of the catalyst dosage, the mole ratio of ProOH to ProAc, the reaction temperature, the stirrer speed on the conversion of ProAc were discussed under the condition of eliminating both internal and external mass transfer resistances. The catalyst dosage of 15 g, the ProOH to ProAc mole ratio of 1.2, the reacticn temperature of 80℃ and the stirrer speed of 400 r/min were the optimum operating conditions, under which the parameters of reaction kinetics, i.e, reaction activation energy Eo = 40.35 kJ/mol and pre-exponential factor k0=2.16×103 L/（mol·min） were obtained. The influences of the feed temperature and the stage number of each section on the purity of product were discussed as the parameters obtained were applied in steady-state simulation. The feed temperature of 70℃, 2 trays in rectifying section, 21 trays in reaction section and 11 trays in stripping section were the optimized operating conditions, under which the product n-propyl propionate of above 99.88% of molar fraction was obtained.