面向贵金属高效利用的催化敏感结构设计、制备控制及催化选择加氢性能

The construction of supported noble metal catalysts has been greatly emphasized, considering the efficiency and economy of noble transitional metals in industrial practical applications. The catalytic-sensing structures have shown great effects on the catalytic performance of noble metal catalysts. However, the properties of noble metal catalysts prepared by traditional impregnation method are not fully reproducible because of high surface tension of water during the subsequent drying and calcination process. Nowadays, it remains a challenge to synthesize noble metal catalysts with controllable catalytic-sensing structures for actual practical applications. Investigation on the multi-scale structures will play an important role in designing, scaling up, controlling, and optimizing chemical engineering processes. The development of protocols for the multi-scale structures of supported metal catalysts is an important topic in catalysis science and technology. The focus of this project will be on the construction of double-scale microstructure of supported noble metal catalysts such as Pd and Ru catalysts, and their catalysis applications, with the aim of investigating the characters of the double-scale structure of supported metal catalysts and the corresponding interactions between the double-scale structures. Layered double hydroxides (LDHs) are a class of synthetic anionic clays. The flexibility in composition allows LDHs with an interesting opportunity for developing new catalysts, catalyst precursors, or catalyst supports with a tailored structure-design, controlled accessibility to the catalytic sites and properties. By taking advantage of this feature it should be possible to modify the properties of supported metal catalysts by deposition of the active component on the LDHs surface, and hence fabricate the noble metal catalyst with high distribution. Porous alumina was used as a support and sole source of Al3+ for the in-situ growth of LDHs in the pores and on the surface. After a subsequent impregnation of noble metal precursor, a highly dispersed metal nanoparticles catalyst was obtained. Characterization of the resulting catalysts will be researched aimed at understanding the coordination environment of metal ions, oxidation states, and dispersion. The supported metal catalysts will be evaluated in catalyzing some selective hydrogenation reactions, such as the selective hydrogenation of pyrolysis gasoline, and the selective hydrogenation of dimethyl terephthalate to dimethyl cyclohexane-1,4-dicarboxylate. Such a systematic study of structure design, synthesis processing and applications of double-scale microstructure of noble metal catalysts may provide an evident proof for the control of atomic structure, morphology, and chemical ordering for the supported metal catalysts with the purpose of enhancing their catalytic properties and cutting cost for noble transitional metals in industrial practical applications.

本项目依据石化行业在负载型贵金属催化剂材料的高效利用及催化选择加氢方面的技术进步需求，依托于化学工程学科在复杂体系多尺度研究方面的充足积累，从负载型贵金属催化剂材料的催化敏感结构设计、制备控制及催化选择加氢性能研究中提炼出三类关键科学问题，开展相关基础研究：（1）如何根据性能来设计负载型贵金属催化剂材料的微/介尺度催化敏感结构；（2）如何实现以选择加氢性能提高为导向的催化剂材料制备过程控制；（3）催化敏感结构的调控如何影响催化剂材料的选择加氢性能。突破新型负载型钯和钌催化剂材料的关键制备技术，利用多尺度的理论计算揭示层状载体表面性质及其与金属团簇的相互作用机制，探讨微/介尺度催化敏感结构与加氢性能之间的构效关系，并研究其在裂解汽油一段选择加氢、对苯二甲酸二甲酯选择加氢等反应中的催化性能。发展2至3类重要石化加氢反应用贵金属催化剂材料，为实现化石资源的高效清洁转化提供支撑。

本项目依据石化行业在负载型贵金属催化剂材料的高效利用及催化选择加氢方面的技术进步需求，依托于化学工程学科在复杂体系多尺度研究方面的充足积累，从负载型贵金属催化剂材料的催化敏感结构设计、制备控制及催化选择加氢性能研究中提炼出三类关键科学问题，开展相关基础研究：（1）如何根据性能来设计负载型金属催化剂材料的微/介尺度催化敏感结构；（2）如何实现以选择加氢性能提高为导向的催化剂材料制备过程控制；（3）催化敏感结构的调控如何影响催化剂材料的选择加氢性能。突破新型负载型钯、钌、金、镍金属及合金催化剂材料的关键制备技术，利用理论计算揭示层状载体表面性质及其与金属团簇的相互作用机制，研究层状前驱体中还原气氛下金属晶体成核及生长机制，探讨微/介尺度催化敏感结构与加氢性能之间的构效关系，并考察其在裂解汽油一段选择加氢、对苯二甲酸二甲酯选择加氢、苯乙炔选择加氢等反应中的催化性能。发展几种重要石化加氢反应用金属催化剂材料，为实现化石资源的高效清洁转化提供支撑。