Jan Faheem, Yang Min, Zhou Nuodan, Sun XiaoYing, Li Bo
Shenyang National Laboratory for Materials Science, Institute of Metal Research, Chinese Academy of Sciences, Shenyang, Liaoning, China.
School of Materials Science and Engineering, University of Science and Technology of China, Shenyang, Liaoning, China.
Front Chem. 2023 Mar 10;11:1133865. doi: 10.3389/fchem.2023.1133865. eCollection 2023.
HCl-assisted propane dehydrogenation (PDH) is an attractive route for propene production with good selectivity. In this study, the doping of CeO with different transition metals, including V, Mn, Fe, Co, Ni, Pd, Pt, and Cu, in the presence of HCl was investigated for PDH. The dopants have a pronounced effect on the electronic structure of pristine ceria that significantly alters the catalytic capabilities. The calculations indicate the spontaneous dissociation of HCl on all surfaces with a facile abstraction of the first hydrogen atom except on V- and Mn-doped surfaces. The lowest energy barrier of 0.50 and 0.51eV was found for Pd- and Ni-doped CeO surfaces. The surface oxygen is responsible for hydrogen abstraction, and its activity is described by the p-band center. Microkinetics simulation is performed on all doped surfaces. The increase in the turnover frequency (TOF) is directly linked with the partial pressure of propane. The adsorption energy of reactants aligned with the observed performance. The reaction follows first-order kinetics to CH. Furthermore, on all surfaces, the formation of CH is found as the rate-determining step confirmed by the degree of rate control (DRC) analysis. This study provides a decisive description of catalyst modification for HCl-assisted PDH.
盐酸辅助丙烷脱氢(PDH)是一条具有良好选择性的丙烯生产途径。在本研究中,研究了在盐酸存在下,用包括钒、锰、铁、钴、镍、钯、铂和铜在内的不同过渡金属对二氧化铈进行掺杂用于丙烷脱氢的情况。掺杂剂对原始二氧化铈的电子结构有显著影响,从而显著改变其催化能力。计算表明,除了钒和锰掺杂的表面外,盐酸在所有表面上都会自发解离,并能轻松夺取第一个氢原子。在钯和镍掺杂的二氧化铈表面发现了最低的能垒,分别为0.50和0.51电子伏特。表面氧负责夺取氢,其活性由p带中心来描述。对所有掺杂表面进行了微观动力学模拟。周转频率(TOF)的增加与丙烷的分压直接相关。反应物的吸附能与观察到的性能相符。该反应对甲烷遵循一级动力学。此外,通过速率控制度(DRC)分析证实,在所有表面上,甲烷的形成是速率决定步骤。本研究为盐酸辅助丙烷脱氢的催化剂改性提供了决定性描述。