Preparation Of Highly Efficient Co-based Catalyst And Its Catalytic Performance For Transfer Hydrogenation Of Fatty Acid Methyl Ester

Natural fats and oils is an environment-friendly renewable resource,and it can be converted to high value-added chemicals and high-quality fuels through catalytic hydrogenation.The traditional catalytic hydrogenation process requires a large amount of H₂produced from fossil energy.However,the preparation,storage and transportation of H₂ require higher costs.Therefore,researchers gradually pay attention to the catalytic transfer hydrogenation of fats and oils without external H₂.The design of high-efficiency catalysts is the core of this process.Hence,in this thesis,focusing on synthesis of the cheap-efficient transfer hydrogenation catalyst,the influences of the geometric structure and electronic structure of catalyst on the transfer hydrogenation performance were mainly explored systematically.The main research contents are as follows:（1）The structure-activity relationship between the structure of the Co/hydroxyapatite（HAP）catalyst and its catalytic performance was revealed.Five Co/HAP catalysts prepared by deposition-precipitation and impregnation methods were used to catalyze the transfer hydrogenation of methyl stearate to produce stearyl alcohol.Multi-characterizations revealed that the Co/HAP catalysts prepared by incipient wetness impregnation method showed strong electron transfer ability and metal-support interaction,and performed the best catalytic performance in the transfer hydrogenation of methyl stearate.（2）The nature of the active sites on the surface of Co/HAP catalysts was explored.Through changing the H₂ reduction temperature,the catalyst surface composition was successfully modified.XRD and XPS characterizations confirmed that the Co⁰/Co^δ+active sites of Co/HAP catalyst synergistically catalyzed the catalytic transfer hydrogenation of methyl stearate to octadecanol.And there was an optimal H₂ reduction temperature（650°C）and Co⁰/Co^δ+ratio（0.32）.In addition,we analyzed the influence of different reaction conditions on transfer hydrogenation of methyl stearate in detail,and revealed the reaction mechanism.（3）The high activity Co-Ni/HAP bimetallic catalyst was designed.We prepared the Co-Ni/HAP bimetallic catalysts and used them to catalyze the transfer hydrogenation of methyl stearate to heptadecane.The Co Ni alloy structure formed on the surface of the Co-Ni/HAP catalyst significantly promoted the deep conversion of methyl stearate,thereby increasing the selectivity of heptadecane.In addition,the Co/Ni molar ratio affects the distribution of products.Through the optimization of the Co/Ni molar ratio,it was found that the yield of heptadecane attained the largest（97.6%）when the Co/Ni molar ratio was equal to 5:5.