基于密度泛函理论的CO2 对NO 异相还原影响的机理研究
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第 49 卷 第 9 期 2021 年 9 月
DOI: 10.1016/S1872-5813(21)60088-9
燃料化学学报 Journal of Fuel Chemistry and Technology
Vol. 49 No. 9 Sept. 2021
基于密度泛函理论的 CO2 对 NO 异相还原影响的机理研究
ZHOU Sai ，LIU Hu* ，YU Peng-fei ，CHE De-fu
（State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China）
Abstract: In order to obtain the mechanism of the effect of CO2 on the NO heterogeneous reduction, density functional theory (DFT) was adopted to investigate the interactions between char and NO with the participation of CO2. The armchair configuration composed with several aromatic ring clusters was selected as the carbonaceous surfaces. Geometric optimizations were carried out at the B3LYP-D3/6-31G(d) level. Energies of optimized geometries were calculated at the B3LYP-D3/def2-TZVP level. The results show that, the surface carbonyl groups produced by the adsorption of CO2 combine with the adsorbed NO to desorb CO2, thereby providing adjacent carbon active sites for subsequent NO adsorption and N2 desorption. Thermodynamic studies show that the exothermic heat of this reaction is 853.9 kJ/mol, and the highest energy barrier is 297.0 kJ/mol without the participation of CO2, but the exothermic heat of this reaction is 593.7 kJ/mol, and the highest energy barrier is 214.1 kJ/mol with the participation of CO2. Kinetic studies show that over the temperature range of 298.15 –1800 K, the reaction rate constants of rate-limiting steps are calculated with conventional transition state theory. The rate constant with the participation of CO2 is higher than that without the participation of CO2. In summary, CO2 plays a promoting role in interacting with NO and char and reducing energy barrier to form N2 directly. Key words: CO2；NO；heterogeneous reduction；density functional theory
CO2 参与条件下，反应放出 593.7 kJ/mol 的热量，决速步能垒为 214.1 kJ/mol。动力学研究表明，在 298.15–1800 K 的温度
下，CO2 参与条件下的反应速率常数大于无 CO2 参与条件下的反应速率常数。综合热力学和动力学研究结果发现，CO2
对 NO 的异相还原反应具有促进作用。
关键词：二氧化碳；一氧化氮；异相还原；密度泛函理论
中图分类号： TQ534.9
文献标识码： A
Application of density functional theory on the NO-char heterogeneous reduction mechanism in the 法 。 研 究 表 明 ， CO2 吸 附 后 形 成 的 羰 基 与 吸 附 态 NO 反 应 生 成 CO2， 继 而 CO2 脱 附 为 后 续 NO 吸 附 及
N2 脱附提供邻近的碳活性位点。热力学研究表明，无 CO2 参与条件下，反应放热 853.9 kJ/mol，决速步能垒为 297.0 kJ/mol；
周 赛 ，刘 虎* ，于鹏飞 ，车得福
（西安交通大学 动力工程多相流国家重点实验室，陕西 西安 710049）
摘 要：为深入理解 CO2 对 NO 异相还原的影响，本研究基于密度泛函理论，对 CO2 参与下的煤焦-NO 异相还原反应机理
进 行 研 究 ， 并 选 取 armchair 苯 环 模 型 模 拟 焦 炭 表 面 。 结 构 优 化 采 用 B3LYP-D3/6-31G(d) 方 法 ， 单 点 能 计 算 采 用 B3LYP-
DOI: 10.1016/S1872-5813(21)60088-9
燃料化学学报 Journal of Fuel Chemistry and Technology
Vol. 49 No. 9 Sept. 2021
基于密度泛函理论的 CO2 对 NO 异相还原影响的机理研究
ZHOU Sai ，LIU Hu* ，YU Peng-fei ，CHE De-fu
（State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China）
Abstract: In order to obtain the mechanism of the effect of CO2 on the NO heterogeneous reduction, density functional theory (DFT) was adopted to investigate the interactions between char and NO with the participation of CO2. The armchair configuration composed with several aromatic ring clusters was selected as the carbonaceous surfaces. Geometric optimizations were carried out at the B3LYP-D3/6-31G(d) level. Energies of optimized geometries were calculated at the B3LYP-D3/def2-TZVP level. The results show that, the surface carbonyl groups produced by the adsorption of CO2 combine with the adsorbed NO to desorb CO2, thereby providing adjacent carbon active sites for subsequent NO adsorption and N2 desorption. Thermodynamic studies show that the exothermic heat of this reaction is 853.9 kJ/mol, and the highest energy barrier is 297.0 kJ/mol without the participation of CO2, but the exothermic heat of this reaction is 593.7 kJ/mol, and the highest energy barrier is 214.1 kJ/mol with the participation of CO2. Kinetic studies show that over the temperature range of 298.15 –1800 K, the reaction rate constants of rate-limiting steps are calculated with conventional transition state theory. The rate constant with the participation of CO2 is higher than that without the participation of CO2. In summary, CO2 plays a promoting role in interacting with NO and char and reducing energy barrier to form N2 directly. Key words: CO2；NO；heterogeneous reduction；density functional theory
CO2 参与条件下，反应放出 593.7 kJ/mol 的热量，决速步能垒为 214.1 kJ/mol。动力学研究表明，在 298.15–1800 K 的温度
下，CO2 参与条件下的反应速率常数大于无 CO2 参与条件下的反应速率常数。综合热力学和动力学研究结果发现，CO2
对 NO 的异相还原反应具有促进作用。
关键词：二氧化碳；一氧化氮；异相还原；密度泛函理论
中图分类号： TQ534.9
文献标识码： A
Application of density functional theory on the NO-char heterogeneous reduction mechanism in the 法 。 研 究 表 明 ， CO2 吸 附 后 形 成 的 羰 基 与 吸 附 态 NO 反 应 生 成 CO2， 继 而 CO2 脱 附 为 后 续 NO 吸 附 及
N2 脱附提供邻近的碳活性位点。热力学研究表明，无 CO2 参与条件下，反应放热 853.9 kJ/mol，决速步能垒为 297.0 kJ/mol；
周 赛 ，刘 虎* ，于鹏飞 ，车得福
（西安交通大学 动力工程多相流国家重点实验室，陕西 西安 710049）
摘 要：为深入理解 CO2 对 NO 异相还原的影响，本研究基于密度泛函理论，对 CO2 参与下的煤焦-NO 异相还原反应机理
进 行 研 究 ， 并 选 取 armchair 苯 环 模 型 模 拟 焦 炭 表 面 。 结 构 优 化 采 用 B3LYP-D3/6-31G(d) 方 法 ， 单 点 能 计 算 采 用 B3LYP-