生物质再燃异相还原NO的分子模拟

基于密度泛函理论和过渡态理论,在分子水平上对焦炭异相还原NO以及碱金属钠的作用机理进行探究。结合单点能的零点能校正以及过渡态的虚频验证,发现钠能够有效促进焦炭对于第一个NO分子的吸附。尽管钠不能改变反应步骤,但可将焦炭异相还原NO决速步的活化能由121.04 kJ/mol降至100.62 kJ/mol;钠的存在使焦炭异相还原NO的指前因子增大且反应速率加快,增加了焦炭边缘的活性位点,强化了焦炭对于NO的异相还原性能。

Molecular simulation study of NO heterogeneous reduction by biomass reburning

A molecular modeling study based on density functional theory (DFT) and transition state theory (TST) was performed to investigate the effect of Na on the NO heterogeneous reduction by char; zero point energy correction was considered and the transition states was confirmed by frequency analysis. The results show that Na can effectively promote the adsorption of first NO molecule on to the char. The presence of Na cannot change the reaction steps, but reduce the activation energies of rate-determining steps from 121.04 kJ/mol to 100.62 kJ/mol. Moreover, the presence of Na can increase the pre-exponential factors as well as the reaction rate, meaning more active sites and enhanced catalytic performance of char in NO reduction.