Yang Chengsheng, Mu Rentao, Wang Guishuo, Song Jimin, Tian Hao, Zhao Zhi-Jian, Gong Jinlong
Key Laboratory for Green Chemical Technology of Ministry of Education , School of Chemical Engineering and Technology , Tianjin University , Collaborative Innovation Center of Chemical Science and Engineering , Tianjin 300072 , China . Email:
Chem Sci. 2019 Feb 11;10(11):3161-3167. doi: 10.1039/c8sc05608k. eCollection 2019 Mar 21.
Oxide-supported Rh nanoparticles have been widely used for CO hydrogenation, especially for ethanol synthesis. However, this reaction operates under high pressure, up to 8 MPa, and suffers from low CO conversion and alcohol selectivity. This paper describes the crucial role of hydroxyl groups bound on Rh-based catalysts supported on TiO nanorods (NRs). The RhFeLi/TiO NR catalyst shows superior reactivity (≈15% conversion) and ethanol selectivity (32%) for CO hydrogenation. The promoting effect can be attributed to the synergism of high Rh dispersion and high-density hydroxyl groups on TiO NRs. Hydroxyls are proven to stabilize formate species and protonate methanol, which is easily dissociated into CH , and then CO obtained from the reverse water-gas shift reaction (RWGS) is inserted into CH to form CHCO, followed by CHCO hydrogenation to ethanol.
负载在氧化物上的铑纳米颗粒已被广泛用于一氧化碳加氢反应，特别是乙醇合成反应。然而，该反应在高达8兆帕的高压下进行，并且存在一氧化碳转化率低和醇选择性低的问题。本文描述了负载在TiO纳米棒（NRs）上的铑基催化剂上结合的羟基的关键作用。RhFeLi/TiO NR催化剂在一氧化碳加氢反应中表现出优异的反应活性（转化率约为15%）和乙醇选择性（32%）。这种促进作用可归因于TiO NRs上高铑分散度和高密度羟基的协同作用。羟基被证明能稳定甲酸盐物种并使甲醇质子化，甲醇易于解离成CH ，然后通过逆水煤气变换反应（RWGS）得到的一氧化碳插入CH 中形成CHCO*，随后CHCO*加氢生成乙醇。
