邻苯二甲酸二丁酯合成的动力学研究

Research on the Kinetics of the Synthesis of Dibutyl Phthalate

采用高效液相色谱法测定了邻苯二甲酸酐(A)与正丁醇(B)合成邻苯二甲酸二丁酯(DBP)反应过程中的产品分布。研究了其反应机理,第一步,自A生成单酯酸(R)是快反应,第二步自R生成DBP是慢反应。建立了分水条件下酯化合成反应的反应动力学模型,试验数据表明DBP的合成表现为二级不可逆反应,测出第二步反应速率常数k2=0.000 7 L.mol-1.min-1。

During the synthesis process of dibutyl phthalate（DBP） from phthalic anhydride （A）and butyl alcohol（B） by HPLC, the product distributions were measured. The reaction mechanism was studied. The first step, the formation of monoisooctyl terephthalate acid（R） from A and B was a faster step, and the second step, formation of DBP from R and B was a low step. Under the condition of separation of water, the reaction kinetics model of esterification carbonylation was established. Based on the experimental data, the synthetic reaction appeared to be the second order and the frequency factor was k2 = 0.000 7 L·mol^-1·min^-1.