Immobilization Of Task-specific Ionic Liquids On MOR Zeolite Membrane: An Novel Catalytic Membrane Reactor For Ketal Reaction

Since membrane catalytic reaction process which combine with inorganicmembrane and catalytic reaction is considered to be one of the three developmentdirections of the catalytic discipline in future, membrane reactor (MR) has broadapplication prospects in the chemical industries catalysis. However, the design,simulation and extensive application of catalytic membrane reactor (CMR) are stillfaced with many difficulties due to the rigorous coupling between catalyst andinorganic membrane. The design approach of catalyst in membrane is the key factor todetermine the proceeding of CMR. Besides, environmentally friendly catalyst withhigh catalytic activity is also highly conceived to replace mineral acid catalyst, suchas H2SO4. Furthermore, the ketalization reaction was chosen as the research objectowing to its widespread popularity. It is very important to thoroughly study thecoupling effect derived from reaction and separation, to explore a new reactiveseparation processes based on CMR for ketalization. Through these efforts, it is notonly effective to enhance the integration efficiency, but also changes the traditionalketalization technology and matches the aim of energy saving and emission reduction.The present work aimed at the research of green production of cyclohexanoneglycol ketal via the membrane catalysis process. Detail research sections aresummarized as follows:The first part of the thesis concerns the design of the BAILs with differentcations and the test of their activity. First, several BAILs composed of differentcations were synthesized and used as catalysts for the ketalization reaction. It is foundthat the catalytic activities of BAILs are mainly relevant to its acidity. The strongeracidity the BAILs have, the higher catalytic activities are. Second, the kinetics ofketalization reaction were studied systemically. A pseudo-homogeneous (PH) kineticmodel was utilized to correlate the experimental data. It is validated from thecomparison between experimental data and the PH model values that the PH modelcan give a good representation of the ketalization kinetic behavior at a low catalystloading. The optimization of reaction conditions were reaction temperature of50°C,catalyst loading of0.5%w/w and molar ratio of the reactants of1.5:1. The results of recycling of BAILs demonstrated that [Hpy][HSO4] could be recycled for up to fivetimes with no appreciable decrease in the conversion of cyclohexanone.The second part of the thesis concerns the preparation of MOR zeolite supportedSO3H-functionalized BAIL and its used as an efficient heterogeneous catalyst forketalization. The catalytic performance tests demonstrated that the catalystBAIL@MOR exhibited excellent catalytic activity compared with homogeneouscatalysts such as [BSmim][HSO4] and H2SO4. The optimization of reaction conditionswere reaction temperature of50°C, molar ratio of the reactants of1:1and catalystloading of0.5%w/w. Besides, the characterization results of XRD, SEM, FT-IR,TG-DTG and N2adsorption-desorption suggested that the BAIL was successfullyimmobilized on the surface of MOR zeolite by covalent bonds.The third part of the thesis concerns supporting BAILs into the MOR zeolitemembrane as CMR for the production of cyclohexanone glycol ketal. The catalyticperformance tests demonstrated that the CMR coated with BAILs showed highercatalytic activity (yield60%) than simple MOR zeolite membrane (yield15%), whichup45%after6h. Besides, the permeation analysis displays a flux of0.2kg m-2h-1together with a separation factor of660for water/organic mixture. Characterizationresults of XRD and SEM also suggested that the BAIL was successfully immobilizedon the surface of MOR zeolite membrane.