Meng Xu, Wu Guiying, Cheng Xiaojie, Wang Jing, Peng Aoqiang, Liang Tingyu, Jin Fang
Key Laboratory for Green Chemical Process of Ministry of Education, Hubei Novel Reactor & Green Chemical Technology Key Laboratory, School of Chemical Engineering and Pharmacy, Wuhan Institute of Technology, Wuhan, Hubei 430205, People's Republic of China.
Research Institute of Petroleum Processing, Sinopec, Beijing 10083, People's Republic of China.
Langmuir. 2023 Mar 28;39(12):4427-4438. doi: 10.1021/acs.langmuir.3c00083. Epub 2023 Mar 13.
The titanosilicate zeolite with a MWW topology structure was synthesized by the atom-planting method through the dehydrochlorination of the hydroxyl group in the deboronated ERB-1 zeolite (D-ERB-1) and TiCl, and Au was further loaded with the deposition precipitation method to apply for the ethane direct dehydrogenation (DH) and dehydrogenation of ethane in the presence of O (O-DH). It was found that Au nanoparticles (NPs) below 5 nm exhibited good activity for ethane direct dehydrogenation and O-DH. The addition of titanium can not only anchor more Au but also make Au have a more dispersed homogeneous distribution. The ethane O-DH catalytic performances of Au-loaded Ti-incorporated D-ERB-1 (Ti-D-ERB-1) were compared to those of Au-loaded ZnO-D-ERB-1 and pure silicate D-ERB-1. The results confirm that ethane O-DH catalyzed by Au-Ti paired active sites is a tandem reaction of catalytic ethane DH and selective H combustion (SHC) of generated H. According to the experimental results and calculated kinetic parameters, such as the activation energy of DH and SHC reaction heat of O-DH, SHC catalyzed by the Au/Ti-D-ERB-1 catalyst containing the Au-Ti active site can not only break the ethane dehydrogenation thermodynamic equilibrium limitation to improve the ethylene yield but also suppress the CO and CO selectivity.
通过原子植入法，以脱硼的ERB-1沸石（D-ERB-1）中的羟基与TiCl进行脱氯化氢反应，合成了具有MWW拓扑结构的钛硅沸石，然后采用沉积沉淀法进一步负载Au，用于乙烷直接脱氢（DH）以及在O存在下乙烷的脱氢反应（O-DH）。研究发现，粒径小于5 nm的Au纳米颗粒（NPs）对乙烷直接脱氢和O-DH表现出良好的活性。钛的加入不仅能锚定更多的Au，还能使Au具有更分散的均匀分布。将负载Au的含钛D-ERB-1（Ti-D-ERB-1）的乙烷O-DH催化性能与负载Au的ZnO-D-ERB-1和纯硅酸盐D-ERB-1的性能进行了比较。结果证实，由Au-Ti配对活性位点催化的乙烷O-DH是催化乙烷DH和生成的H的选择性燃烧（SHC）的串联反应。根据实验结果和计算得到的动力学参数，如DH的活化能和O-DH的SHC反应热，含有Au-Ti活性位点的Au/Ti-D-ERB-1催化剂催化的SHC不仅可以打破乙烷脱氢的热力学平衡限制以提高乙烯产率，还能抑制CO和CO2的选择性。
