| CMO is an important fine intermediate, which is conventionally used as material in perfumey, medicine and insecticide. The method of traditionally homogeneous chemical reduction is disadvantageous of high cost, difficult separation of products and environmental pollution, but heterogeneous catalytic technology can solve the problems. It is a challenge to hydrogenate on C=O in a molecule with C=C and C=O. The work is an important part of task, study on heterogeneous catalysts of selective hydrogenation of α,β- unsaturated aldehyde to α-β unsaturated alcohol supported by National Natural Science Foundation (No.20266001). The unnoble metal Cobalt catalysts were selected in the reaction system. The study was both of theoretical significance of selective hydrogenation and practical significance of making full of abound bay oil resources in GuangXi province.In the paper transition metal- cobalt (Co) is selected for main ingredient in catalyst, and diatomite, a kind of highly microporous material and having a surface of strong acidity, is picked out to be the support based on catalyst Co/γ-A12O3 that is reported in the literature, repeatedly. Co/ diatomite is prepared by the means of impregnation. Promoting agent-iron (Fe,III) is singled out and introduced as a modification into the Co-based catalyst by the way of step- impregnation. The activity and selectivity of catalyst Co- Fe/ diatomite is investigated, and the effects of promoting catalyst as well. Catalysts' preparation and condition of hydrogenationreaction is optimized. Techniques such as synthesis thermo-analysis (TG, DTG, DTA), FT-IR, PLS, XRD, SEM etc. are used for characterization when the structure of catalyst Co/ diatomite is compared with that of Co/r-A12O3. The structural properties of catalysts are related with the datum of its selectivity and activity, and laws of structural variation on catalvtic performances are also revealed.It is found through selectivity of supports that reaction conversion of CMA over 9%(wt) Co/ diatomite is 52.69%, increased by 5.8% in contrast with Co/y-A12O3 (46.98%), and reaction selectivity of CMO over former is 82.76%, increased by 1.88% in contrast with later (80.88%). While reaction conversion of CMA over 12%(wt) Co/ diatomite is 64.3%, increased by 9.26% in contrast with Co/r-A12O3 (55.04%), and reaction selectivity of CMO over former is 88.07%, increased by 31.7% in contrast with later (56.37%)after catalysts, that is Co/ diatomite and Co/y-A12O3, are tested and samples are successively analyzed in the same following terms, inside reactor temperature at 427K, liquid flow capacity dosage of 0.08ml/min,H2 pressure at 2.06-2.10Mpa,H2 flow capacity in 15~18ml/min, cold trap temperature <278K, catalyst dosage about 3 ml and mess round 2g, reacting for 1 hour. It is observed from the experiment that the best loading threshold of Co/ diatomite is 12%; optimum calcination temperature and optimum reducing temperature are 673K and 723K,respectively.In the promoter-selecting process, promoting catalyst-Fe (III) is found to be efficient for improving catalytic activity on the premise that doesn't decline high selectivity, and optimum dosage of iron used in catalyst is n Fe: n Co =0.20(Mole. Ratio). If keeping that, CMA conversion could reach 79.62%, and CMO selectivity and yield could reach 80.3% and 63.93%, respectively. To compare without introducing Fe (III), the conversion of CMA is increased by 18.93%, the selectivity of CMO is decreased by 4.56%, and the yield of CMO is increased by 12.44%. Studies on preparation of catalyst have shown that Co- Fe/ diatomite catalyst have a good performance under the condition of calcination at 673K and reducing at 723K. Apart from that, supersonic technology is applied into the preparation of catalyst and it isfound that active compositions like Co, Fe can be dispersed effectively, and the percentage of CMA conversion and CMO selectivity goes up as a result of the cavitations effect. Further research demonstrates that introduction of Fe facilitates reduction of Co-based catalyst, improve...
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