Platinum clusters stabilized by zincosilicate zeolite for efficient propane dehydrogenation  

利用硅酸锌沸石稳定铂簇以实现高效丙烷脱氢

作　　者：Hao Liu Ying Zhang Liyang Liu Tianxiang Chen Xingcong Zhang Peng Hu Chao Xiong Jie Zhou Hao Zhang Lihui Dong Tsz Woon Benedict Lo Bing Nan Xiaohui He Hongbing Ji 刘浩;张颖;刘立扬;陈天翔;张兴聪;胡鹏;熊超;周杰;张浩;董丽辉;劳子桓;南兵;何晓辉;纪红兵(中山大学化学学院,精细化工研究院,生物有机合成化学教育部重点实验室,广东广州510275;广西大学化学化工学院,广西石化资源加工与过程强化技术重点实验室,广西南宁530004;上海高等研究院,上海同步辐射装置,上海200120;香港理工大学应用生物与化学技术系,化学生物学与药物发现国家重点实验室,中国香港红磡;浙江工业大学化工学院,绿色石油加工与轻烃转化研究院,绿色化工合成技术国家重点实验室育种基地,浙江杭州310014;广东省热敏化学品合成与分离技术研究中心,广东广州510006)

机构地区：[1]Key Laboratory of Bioinorganicand Synthetic Chemistry of Ministry of Education,Fine Chemical Industry Research Institute,School of Chemistry,IGCME,Sun Yat-sen University,Guangzhou 510275,Guangdong,China [2]Guangxi Key Laboratory of Petrochemical Resource Processing and Process Intensification Technology,School of Chemistry and Chemical Engineering,Guangxi University,Nanning 530004,Guangxi,China [3]Shanghai Synchrotron Radiation Facility,Shanghai Advanced Research Institute,Shanghai 200120,China [4]State Key Laboratory of Chemical Biology and Drug Discovery,Department of Applied Biology and Chemical Technology,The Hong Kong Polytechnic University,Hunghom,Hong Kong,China [5]State Key Laboratory Breeding Base of Green-Chemical Synthesis Technology,Institute of Green Petroleum Processing and Light Hydrocarbon Conversion,College of Chemical Engineering,Zhejiang University of Technology,Hangzhou 310014,Zhejiang,China [6]Guangdong Technology Research Center for Synthesis and Separation of Thermosensitive Chemicals,Guangzhou 510006,Guangdong,China

出　　处：《Chinese Journal of Catalysis》2025年第4期208-219,共12页催化学报(英文)

基　　金：国家重点研发计划纳米技术专项(2020YFA0210902);广东省杰出青年自然科学基金(2022B1515020035);国家自然科学基金(22422815,22078371,U22A20428,21938001);山西省科技创新团队专项基金(202304051001007);广东省功能分子工程基础研究中心、化学化工广东省实验室(1922010).

摘　　要：Dispersing metals from nanoparticles to clusters is often achieved using ligand protection methods,which exhibit unique properties such as suppressing structure-sensitive side reactions.However,this method is limited by the use of different metal precursor salts corresponding to different ligands.An alternative approach,the ion exchange(IE)method,can overcome this limitation to some extent.Nevertheless,there is still an urgent need to address the stabilization of metals(especially precious metals)by using IE method.Here,we reported a Pt cluster catalyst prepared mainly by anchoring Pt atoms via O located near the framework Zn in zincosilicate zeolites and riveted by zeolite surface rings after reduction(reduced Pt/Zn-3-IE).The catalyst can achieve an initial propane conversion of 26%in a pure propane atmosphere at 550℃and shows little deactivation even after 7.5 d of operation.Moreover,the alteration of catalyst by the introduction of framework Zn was also highlighted and interpreted.利用配体保护法将金属物种封装在沸石内部或高度分散在沸石表面,可用于提升烷烃脱氢(ADH)效率.但受限于金属盐与配体的特异性匹配(如乙二胺、二乙烯三胺、四乙烯五胺和硫醇配体等),导致制备过程相对繁琐,从而限制该方法的应用.相较之下,离子交换(IE)法由于无需配体保护,展现出了优异的金属负载灵活性.此外,Zn对Pt的电子和几何结构极佳的修饰作用已经获得了实验与理论计算的双重认证,受到了许多研究人员的关注.但是,沸石框架Zn对活性位点Pt的影响还有待深入研究.IE法使用的载体包括各种含框架铝的沸石(如CHA,BEA,MOR,SSZ-13,SAPO-34和ZSM-5等),但这些含铝沸石的硅/铝比率较低,具有较强的布朗斯台德(B)酸性质,易导致深度裂解反应.此外,沸石也需要合适的孔道来提升烷烃的传质效率来确保高效脱氢.因此,用于ADH的此类催化剂受到载体的诸多限制,只有In-CHA,Zn/H-MFI和Co-SAPO-34等少数几种催化剂被用于ADH反应.但由于采用非贵金属作为活性中心,其催化性能相对较差.本文从不含铝的MFI沸石载体出发,利用含框架Zn的硅酸锌中的Si-OH-Zn(弱B酸位点)和孤立的Si-OH来稳定贵金属Pt物种,从而在还原后形成沸石环铆钉的Pt簇催化剂.具体而言,采用一步水热法将Zn和Na同时引入到沸石中,其中Zn掺入沸石骨架,Na^(+)进入了沸石孔道内.随后,采用离子交换法实现对Pt的负载.通过引入Zn和Na^(+)对沸石中的环境进行调节,两者协同促进了Pt的锚定,并极大程度的抑制了Pt的团聚.均匀Pt-沸石催化体系作为L酸位点无需第二金属合金化即可实现丙烷的高效转化,并可以清晰地了解结构、酸性位点和催化作用.最佳的Pt/Zn-3-IE催化剂在600℃,25%的丙烷气氛下实现了62%的初始丙烷转化率和97%的丙烯选择性,连续运行20小时测性能无衰减.而纯丙烷气氛中,在550°C保持180小时稳定运行,优于大多数的前�

关 键 词：Zincosilicate zeolite Acid-site identification Rivet effect Pt clusters Propane dehydrogenation 

分 类 号：O643.36[理学—物理化学]