异丙醇一步法联产甲基异丁基酮和二异丁基酮的催化剂性能评价

The Catalyst Performance Evaluation for One-step Synthesis of Methyl Isobutyl Ketone and Diisobutyl Ketone from Isopropanol

采用等温积分反应器,在常压、250℃和液相空速1h-1条件下,对国产Cu-ZnO-Al2O3复合型多功能催化剂上、异丙醇一步法联产甲基异丁基酮(MIBK)和二异丁基酮(DIBK)的反应性能进行了实验评价.结果表明,该催化剂对MIBK和DIBK的生成具有良好的初始活性和选择性;但随运行周期的延长,尽管其脱氢能力和对异丙醇与丙酮缩合脱水生成MIBK的能力相对稳定,但对MIBK与异丙醇缩合脱水生成DIBK的能力明显降低.反应物相中少量丙酮的存在有利于催化剂活性、MIBK和DIBK选择性的提高,但过量丙酮的存在对合成反应不利.因此,活性组分之间协同作用功能的进一步设计和适宜合成条件的选取,是提高异丙醇一步法联产MIBK和DIBK合成催化剂性能的两条重要途径.

The reaction performance evaluation experiments of a domestic Cu-ZnO-Al 2O 3 complex bifunctional catalyst for one-step synthesis of methyl isobutyl ketone (MIBK) and diisobutyl ketone (DIBK) from isopropanol were carried out in an isothermal integral reactor under atmospheric pressure, 250 ℃ and liquid space velocity of 1 h -1. The results show that the Cu-ZnO-Al 2O 3 catalyst here has a good initial activity and selectivity for MIBK and DIBK synthesis. With the run time increasing, however, DIBK formation rate from MIBK and isopropanol condensation dehydration has an obvious drop, though isopropanol dehydrogenation rate and MIBK formation rate from isopropanol and acetone condensation dehydration are still relatively steady. A small quantity of acetone in feed material is advantageous to the increase of the catalyst activity, selectivity of MIBK and DIBK, but excess acetone will make against the synthesis reaction process. Therefore, the further adjustment of synergistic performance among various active components in Cu-ZnO-Al 2O 3 catalyst and the determination of the reasonable operating condition maybe are two important pathways to enhance the catalyst performance for one-step synthesis of MIBK and DIBK from isopropanol.