硫酸催化合成邻苯二甲酸二甲酯的动力学

Kinetics on Synthesis of Dimethyl Phthalate Catalyzed with Sulfuric Acid

在工业生产过程所涉及的温度条件下对浓硫酸催化合成邻苯二甲酸二甲酯的化学反应动力学进行了实验研究,测定了两个实验温度(90℃,100℃)下硫酸催化剂浓度为0.2%～0.9%时反应中各物质的浓度变化,获得了该温度下和催化剂浓度范围内的反应动力学表达式和反应速率常数。实验结果表明,实验条件下的反应速率对邻苯二甲酸单甲酯,甲醇,邻苯二甲酸二甲酯和水均为二级反应,反应速率常数随硫酸浓度基本呈线性增长,正反应活化能约为68.941kJ/(mol·K)

The chemical reaction kinetics on synthesis of dimethyl phthalate catalyzed by sulfuric acid was studied experimentally in the temperature range of industrial production process. The concentration change of each substance for a certain concentration range （0.2%-0.9%） under two temperatures （9℃, 100℃） was measured and corresponding kinetics equation and reaction rate constants were obtained. The experimental results showed that the reaction was a first-order to monomethyl phthalate, methanol, dimethyl phthalate and water under the experimental conditions, the reaction rate constant increased linearly with sulfuric acid concentration and the activation energy of positive reaction was about 68.941 kJ/（mol.K）.