Dehydrogenation and dehydration of formic acid over orthorhombic molybdenum carbide.
Dehydrogenation and dehydration of formic acid over orthorhombic molybdenum carbide.
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DOI：
10.1016/j.cattod.2021.04.011
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发表时间：
2022-02-15
期刊：
影响因子：
5.3
通讯作者：
中科院分区：
文献类型：
--
作者：
甲酸在β-Mo2C上的吸附是放热的，且具有平行于表面的构型。一旦被吸附，热力学有利于H-COOH键的断裂形成CO。CO强烈地结合在表面，潜在地毒化了催化剂。因此，动力学有利于连续生成CO2的脱氢机理。用与时间无关的密度泛函理论研究了甲酸在β-Mo2C(100)催化剂上的脱氢和脱水反应。计算了这两种机制的能量学，并用过渡态理论讨论了热化学和动力学。随后，考虑间歇反应器模型，对系统进行了微观动力学建模。反应的势能图表明，热力学上有利于H-COOH的裂解生成CO，但动力学表明，脱氢机理较快，CO2的生成是连续的。在程序升温脱附过程中，还分析了HCOOH在表面的吸附效应，在350K以下进行了转化，观察到CO2的选择性约为100%，与实验结果一致。
Formic acid (HCOOH) adsorption on β-Mo2C is exothermic and favours a configuration parallel to the surface. Once adsorbed, thermodynamics favour cleavage of the H—COOH bond to form CO. CO bonds strongly to the surface, potentially poisoning the catalyst. Therefore, kinetics favour dehydrogenation mechanism with CO2 continuously formed. The dehydrogenation and dehydration of formic acid is investigated on the β-Mo2C (100) catalyst surface using time independent density functional theory. The energetics of the two mechanisms are calculated, and the thermochemistry and kinetics are discussed using the transition state theory. Subsequently, microkinetic modelling of the system is conducted, considering the batch reactor model. The potential energy landscape of the reaction shows a thermodynamically favourable cleavage of H—COOH to form CO; however, the kinetics show that the dehydrogenation mechanism is faster and CO2 is continuously formed. The effect of HCOOH adsorption on the surface is also analysed, in a temperature-programmed desorption, with the conversion proceeding at under 350 K and desorption of CO2 is observed with a selectivity of about 100 %, in line with the experimental reports.
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影响因子：
4.4
作者：
Eyring, H
通讯作者：
Eyring, H
影响因子：
3.6
作者：
Darby, Matthew T.;Sykes, E. Charles H.;Stamatakis, Michail
通讯作者：
Stamatakis, Michail
影响因子：
13.1
作者：
Barlocco, Ilaria;Capelli, Sofia;Villa, Alberto
通讯作者：
Villa, Alberto
影响因子：
5
作者：
Carrales-Alvarado, D. H.;Dongil, A. B.;Rodriguez-Ramos, I
通讯作者：
Rodriguez-Ramos, I
影响因子：
2.7
作者：
AAS, N;LI, YX;BOWKER, M
通讯作者：
BOWKER, M