Ru-Mn/γ-Al_2O_3催化剂制备及合成环己烷二甲酸二异壬酯工艺研究

Preparation of Ru-Mn/γ-Al_2O_3 catalyst and uses in synthesis of DINCH

研究了浸渍法制备的一系列Ru-Mn/γ-Al_2O_3催化剂在邻苯二甲酸二异壬酯(DINP)催化加氢制备环己烷二甲酸二异壬酯(DINCH)反应中的催化性能。通过表征证明了Ru和Mn离子的引入使催化剂的加氢能力增强,因此,Ru-Mn/γ-Al_2O_3催化剂表现出较高的催化活性。考察了催化剂中金属质量分数、焙烧条件和还原条件等因素对催化剂活性的影响,在Ru质量分数为1%、Mn为1%、250℃下焙烧2 h、140℃下还原活化2 h条件下,催化剂活性最高。确定了反应的最佳工艺条件:反应压力为4 MPa,反应温度为120℃,搅拌速度为600 r/min,反应时间为4 h;产物的选择性为100%,收率为99.4%。催化剂重复使用5次产物收率仍能维持在99%以上,表明该催化剂催化加氢DINP制备DINCH有较好的稳定性。

A series of Ru-Mn/γ-Al2O3 catalysts are fabricated through impregnation method using γ-Al2O3 as supporter.The catalytic performance of prepared Ru-Mn/γ-Al2O3 catalysts is investigated through the preparation of diisononyl cyclohexane dicarboxylate（ DINCH） by the hydrogenation of diisononyl phthalate（ DINP）.The structure and property of catalysts are characterized by BET,XRD,SEM and H2-TPD. The characterization results indicate that the catalytic activity of the catalysts is remarkably enhanced due to the addition of Mn and Ru. The influences of the mass concentration of metal in the catalyst,calcination conditions and reduction conditions on the catalyst activity are investigated.The catalysts have the highest activity when the mass concentration of Ru and Mn both are 1%,the calcination lasts for 2 h at 250℃ and the reduction is carried out at 140℃ for 2 h. The optimum reaction conditions for preparation of DINCH are determined as follows： the 1% Ru-1% Mn/γ-Al2O3 catalyst is used,the reaction pressure is4 MPa,the reaction temperature is at 120℃,the stirring speed is set as 600 r·min-1 and the reaction time lasts for 4 h.Under the optimum conditions,the selectivity and yield of DINCH can reach 100% and 99. 4% respectively.The yield of DINCH can still remain above 99% over the catalyst after five times of repeated uses,illustrating that the catalyst exhibits good stability in catalyzing hydrogenation of DINP to make DINCH.