吉林大学于吉红团队报道了沸石中三配位单原子钴促进丙烷脱氢。相关研究成果于2024年3月25日发表于国际一流学术期刊《美国化学会杂志》。

丙烷脱氢（PDH）反应以其对丙烯的高选择性和良好的经济效益，成为最有前途的丙烯生产路线之一。然而，商业PDH工艺通常依赖于昂贵的铂基和有毒的氧化铬基催化剂。探索具有优异催化活性、丙烯选择性和稳定性的，具有成本效益和生态友好性的PDH催化剂具有重要意义，但具有挑战性。

该文中，研究人员发现了一个新的活性中心，即在钼掺杂的silicalite-1沸石中的不饱和三配位钴单元(≡Si–O)CoO(O–Mo)。这种活性比先前报道的钴原子通常四配位的钴基催化剂高出近一个数量级，甚至在类似的操作条件下优于大多数Pt基催化剂。密度泛函理论计算与最先进的表征相结合，揭示了不饱和三配位Co单元在促进丙烷和丙烯脱附的C–H键断裂中的作用。

该工作为未来基于廉价非贵金属催化剂的大规模工业PDH生产开辟了新的机会。

附：英文原文

Title: Tricoordinated Single-Atom Cobalt in Zeolite Boosting Propane Dehydrogenation

Author: Ziqiang Qu, Guangyuan He, Tianjun Zhang, Yaqi Fan, Yanxia Guo, Min Hu, Jun Xu, Yanhang Ma, Jichao Zhang, Weibin Fan, Qiming Sun, Donghai Mei, Jihong Yu

Issue&Volume: March 25, 2024

Abstract: Propane dehydrogenation (PDH) reaction has emerged as one of the most promising propylene production routes due to its high selectivity for propylene and good economic benefits. However, the commercial PDH processes usually rely on expensive platinum-based and poisonous chromium oxide based catalysts. The exploration of cost-effective and ecofriendly PDH catalysts with excellent catalytic activity, propylene selectivity, and stability is of great significance yet remains challenging. Here, we discovered a new active center, i.e., an unsaturated tricoordinated cobalt unit (≡Si–O)CoO(O–Mo) in a molybdenum-doped silicalite-1 zeolite, which afforded an unprecedentedly high propylene formation rate of 22.6 molC3H6 gCo–1 h–1 and apparent rate coefficient of 130 molC3H6 gCo–1 h–1 bar–1 with >99% of propylene selectivity at 550 °C. Such activity is nearly one magnitude higher than that of previously reported Co-based catalysts in which cobalt atoms are commonly tetracoordinated, and even superior to that of most of Pt-based catalysts under similar operating conditions. Density functional theory calculations combined with the state-of-the-art characterizations unravel the role of the unsaturated tricoordinated Co unit in facilitating the C–H bond-breaking of propane and propylene desorption. The present work opens new opportunities for future large-scale industrial PDH production based on inexpensive non-noble metal catalysts.

DOI: 10.1021/jacs.3c12584

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.3c12584