Methyl Isopropyl Ketone And Diethyl Ketone Synthesis Study On ZrO₂-based Catalysts

In this dissertation, the synthesis of methyl isopropyl ketone and diethyl ketone over ZrO2-based catalysts is studied. The factors such as the preparation methods of catalyst and response conditions are investigated to influence on performance of reacting. It is found that ZrO2-MnOx-Zn0 (n(Zr):n(Mn):n(Zn) = 2.0:0.2:2.0) (x=2-4 ) catalyst prepared by coprecipitation shows higher activity and selectivity toward methyl isopropyl ketone and diethyl ketone. Addition of Pd and Na into ZrO2-MnOx-ZnO catalyst enhances the activity and selectivity toward methyl isopropyl ketone and diethyl ketone obviously. The catalyst of 0.25%Pd-0.29%Na/ZrO2-MnOx-ZnO shows better activity and selectivity to methyl isopropyl ketone and diethyl ketone at 643K, 0.1MPa and 1.0h-1. The activity of methyl ethyl ketone is 45.78%. The selectivity of methyl isopropyl ketone and diethyl ketone are up to 44.71%, 33.07% respectively.BET, XRD, CO2-TPD and NH3-TPD experimental results indicate surface nature of ZrO2. Superficial acid and alkaline nature of ZrO2 have remarkable influence to synthesis of methyl isopropyl ketone and diethyl ketone. The results reveal that the surface of ZrO2 plays an important role in formation of methyl isopropyl ketone and diethyl ketone. The higher H2 uptakes on Pd-Na/ZrO2-MnOx-ZnO catalyst are in favor of enhancement in the rate of methyl isopropyl ketone and diethyl ketone synthesis. Only in a suitable acid and alkali location and intensity, it is favorable to synthesis of methyl isopropyl ketone and diethyl ketone. Adding right amount Pd can make the catalyst surface maintain higher H2 absorbing amount to improve synthesizing methyl isopropyl ketone and diethyl ketone. In order to understand the mechanism of systhesis of methyl isopropyl ketone and diethyl ketone and the feasibility of raising methyl isopropyl ketone and diethyl ketone yield, Temperature-Programmed Surface Reaction(TPSR) of adsorbed methanol on Pd-Na/ZrO2-MnOx-ZnO catalyst is carried out. The results of characterization and methyl ethyl ketone and methanol reaction on Pd-Na/ZrO2-MnOx-ZnO show that dehydrogenation, aldol, dehydration and hydrogenation reactions can be simultaneously accomplished on Pd-Na/ZrO2-MnOx-ZnO.This text successfully realize synthesis of methyl isopropyl ketone and diethyl ketone from methyl ethyl ketone route for the first time by one step. And it has developed the multifunctional catalyst of Pd-Na/ZrO2-MnOx-ZnO in success for the first time.