甘油三酯在碱性ZnxAlyO复合氧化物负载的镍基催化剂上的加氢脱氧反应机理及催化剂活性中心的构建

项目名称： 甘油三酯在碱性ZnxAlyO复合氧化物负载的镍基催化剂上的加氢脱氧反应机理及催化剂活性中心的构建

项目编号： No.21506239

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 有机化学

项目作者： 李广慈

作者单位： 中国科学院青岛生物能源与过程研究所

项目金额： 21万元

中文摘要： 甘油三酯的加氢脱氧过程是以动植物油脂为原料制备生物柴油的关键步骤，而加氢脱氧催化剂对于该过程能否顺利进行至关重要。和常用的过渡金属硫化型催化剂相比，过渡金属还原型催化剂所需的反应条件温和，使用时无需硫化，因此近年来受到广泛关注。然而，目前该类催化剂的制备主要以分子筛材料作为载体，裂化活性高、易积碳，影响柴油组分的收率。本研究拟以碱性的锌铝复合氧化物为载体降低催化剂表面的酸性，以提高产物的收率，增强催化剂的抗积碳性能。通过研究甘油三酯转化产生的不同含氧中间产物的转化机制，明确甘油三酯的反应机理和关键单元反应；通过改变制备条件对载体表面的碱性进行调变并与脱氧反应结果进行关联，研究活性金属的结构和催化性能与载体的碱性之间的变化关系；针对关键单元反应，研究载体碱性变化对反应的影响，探明碱性中心的催化作用机理，最终揭示催化剂表面的加氢脱氧催化活性中心，为该类型催化剂的开发和应用提供重要的研究基础。

中文关键词： 甘油三酯；加氢脱氧；复合氧化物；碱性中心；氧空穴

英文摘要： Hydrodeoxygenation of triglycerides is the key process for the preparation of second generation biodiesel from vegetable/animal oil. Particularly, the HDO catalyst is the crucial factor to this process. Compared to conventional supported sulfided transition metal catalysts, supported reduced transition metal catalysts show excellent deoxygenation activity under mild reaction conditions, and are used without sulfurization. Thus, reduced transition metal catalysts have been attracted much attentions in recent years. Most reduced transition metal catalysts, however, have been prepared using zeolite materials as supports, which accelerate the cracking of the product and the coking of the catalyst surface, leading to a low yield of diesel fractions. This project will employ basic Zn-Al composite oxides as supports to decrease the prepared catalyst acidity for increasing diesel fraction yield and enhancing the resistance of carbon deposition. The reaction mechanism of triglycerides and key unit reaction will be identified according to the conversion of oxygen-containing intermediates. The close relationship between the structure and catalytic activity of active metal and the basicity of support will be studied based on the dependence of reaction on the support basicity. Particularly, the effect of active metal and basic support on the conversion of triglycerides, as well as the role of Ni species and basic centers on the catalyst surface will be extensively investigated for exploring the catalytic active centers for hydrogenation and deoxygenation steps. This project is aiming at providing fundamental knowledge for the development and application of these catalysts.

英文关键词： Triglyceride;Hydrodeoxygenation;Composite oxides;Basic center;Oxygen vacancy