Study On MoS₂/C Catalyst For Ethyl Acetate Preparation From Ethanol

In the ways of producing ethyl acetate, the direct synthesis from ethanol hasdrawn more and more attention because of noncoorosive, less-toxic and inexpensivefeatures.A novel MoS2/C catalyst for one-step synthesis of ethyl acetate from ethanol wasinvented. The effects of ATTM loading and calcination conditions on the performanceof the catalyst were investigated;the process conditions were optimized;the stabilityof the catalyst was tested in the optimized conditions;the possible mechanism wasproposed based on the experiment.The results of catalyst preparation indicated that 20% was the best loadingquantity, the higher loading would cause lower ethanol conversion and ethyl acetateselectivity, the performance of catalyst which was calcined in H2 showed bettercatalytic performance than that in N2, NH3 TPD experiments showed that more strongacidic centers were generated when the catalyst was calcined in N2 calcination, it hasmuch relation with the production of byproduct alkenes.The process conditions was optimized as following: reaction temperature rangewas 290℃~300℃, the space velocity range of liquid ethanol was 0.72h-1~1.08h-1.The results of stability tests indicated that the catalyst performed a wellperformance after 90 hours' reaction, the conversion for ethanol was about 65%, theselectivity for ethyl acetate and acetaldehyde was about 82%. SEM, XRD, BET wereused to measure the change of the morphosis, elements composition, phase state andthe surface area. The results indicated that the change was happened on the morphosisand the S/Mo, no obvious change was observed on the phase state, surface area wasreduced after reaction.The preliminary mechanism was proposed based on the experiment, the reactionmechanism was supposed to be: dehydrogenation of ethanol to acetaldehyde, whichwas the first step of the reaction, ethyl acetate was produced via dehydrogenation ofethanol and acetaldehyde.