State Key Laboratory of Coal Conversion, Institute of Coal Chemistry, Chinese Academy of Sciences
University of Chinese Academy of Sciences

联环己烷是一种高储氢密度、低沸点储氢试剂。与联苯加氢相比，苯和环己烯烷基化制环己基苯再加氢是一种有望实现大规模制备联环己烷的途径。在成熟的烷基化技术基础上，需进一步开展高效环己基苯加氢催化剂的研发。本研究首先使用酸化的USY分子筛催化苯和环己烯烷基化至环己基苯，获得100%转化率和产物选择性。进一步通过原子层沉积（ALD）在γ-Al2O3表面预先沉积不同厚度的TiO2膜后再负载铂颗粒制得Pt/TiO2/γ-Al2O3催化剂，研究TiO2膜提升催化剂环己基苯加氢性能机制。TEM、CO脉冲吸附、CO-DRIFTs、准原位XPS、H-D交换和H2-TPR表征显示，与Pt/γ-Al2O3相比，Pt/TiO2/γ-Al2O3催化剂不改变Pt颗粒的分散度，但能够形成新的Pt-TiO2相互作用，提高铂表面电子密度、平面活性位点比例和降低氢溢流能垒，提升环己烷基苯加氢性能。研究为进一步发展联环己烷有机液态储氢试剂提供理论支持。相关金属-载体相互作用调控策略可应用于其他芳香性分子高效加氢催化剂的研制。

Bicyclohexane is a hydrogen storage reagent with high hydrogen density and low boiling point. Compared with the hydrogenation of biphenyl, the alkylation of benzene and cyclohexene to cyclohexylbenzene and hydrogenation is a promising way to prepare cyclohexane on a large scale. The research and development of high-efficiency cyclohexyl benzene hydrogenation catalyst should be further developed based on mature alkylation technology. This paper used an acidified USY molecular sieve to catalyze the alkylation of benzene and cyclohexene to cyclohexylbenzene, which achieved 100% conversion and selectivity. Furthermore, Pt/TiO2/γ-Al2O3 catalyst is prepared by pre-deposition TiO2 film of different thicknesses on γ-Al2O3 surface and then supported with platinum particles by Atomic layer deposition (ALD). The role of TiO2 film in improving the cyclohexylbenzene hydrogenation performance of the catalyst is studied. TEM, CO pulse chemisorption, CO-DRIFTs, quasi-in situ XPS, H-D exchange, and H2-TPR characterization show that compared with Pt/γ-Al2O3, TiO2 thin films on Pt/TiO2/γ-Al2O3 do not change the dispersion of Pt particles, but can form new Pt-TiO2 interactions. The hydrogenation performance of cyclohexylbenzene was improved by increasing the electron density and the proportion of planar active sites on the surface of platinum and reducing the energy barrier of hydrogen spillover. The research provides theoretical support for further bicyclohexane organic liquid hydrogen storage reagent development. The relevant metal-support interaction regulation strategy can be applied to the development of efficient catalysts for other aromatic molecules hydrogenation.

国家自然科学基金 (22072172，22202227)，国家杰出青年科学基金（21825204），中国科学院青年创新促进会（Y2021056），榆林学院与大连清洁能源国家实验室合作基金（YLU-DNL Fund 2022007）和山西省科技创新团队专项资金（202304051001007）资助

刘瑞林, 王森, 孟繁春, 李卓, 杨慧敏, 赵世超, 覃勇, 张斌. 苯和环己烯分步制联环己烷过程催化剂设计及性能提升研究[J]. 燃料化学学报（中英文）, 2024, 52(9): 1290-1298.

LIU Ruilin, WANG Sen, MENG Fanchun, LI Zhuo, YANG Huimin, ZHAO Shichao, QIN Yong, ZHANG Bin. The study of design and performance improvement of catalysts for the stepwise production of bicyclohexane from benzene and cyclohexene[J]. Journal of Fuel Chemistry and Technology, 2024, 52(9): 1290-1298.