DFT study on the reaction mechanism of N2O reduction with CO catalyzed by char. (15th October 2019)

• Record Type: Journal Article
• Authors: Chen, Ping; Gu, Mingyan; Chen, Guang; Liu, Fengshan; Lin, Yuyu
• Is Part Of: Fuel. Volume 254(2019)
• Publication Date: 2019-10-15
• Subjects: Char -- CO -- N2O -- Density functional theory -- Catalysis; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2019.115666
• Languages: English
• ISSNs: 0016-2361

Abstract

Highlights: Char has a significant catalytic effect on N2 O reduction with CO. The catalytic effect of zigzag char is more predominant. CO and char have a synergistic promoting effect on N2 O reduction. C(O) is promoted to decompose into CO2 in the presence of CO. Abstract: The effect of char during the heterogeneous reduction of N2 O by CO has been studied using density functional theory (DFT). The armchair and zigzag configurations with six and seven aromatic ring clusters are selected as the carbonaceous surfaces. The calculation results show that heterogeneous reduction of N2 O by CO on char surface undergoes two stages: N2 O reduction and residual oxygen desorption. Char has a significant catalytic effect on the reduction of N2 O by CO, which not only provides reactive sites for CO and N2 O but also significantly reduces the activation energy of N2 O reduction. On the one hand, the presence of CO significantly reduces the activation energy of N2 desorption on the char surface, and synergize with char to promote N2 O reduction. On the other hand, it significantly reduces the activation energy of CO2 desorption and is beneficial to CO2 release. Char edge types have different catalytic effects on N2 O heterogeneous reduction, and zigzag char is more advantageous in kinetics than armchair char. This study makes contributions to enrich the mechanisms of N2 O reduction during combustion.