Metal-free C2N catalyst with superior H2O/SO2 tolerance for NO reduction with CO during incomplete combustion process

• Published in: Fuel (Guildford) 2023-12, Vol.354, p.129262, Article 129262
• Main Authors: Zhou, Junhui, Li, Didi, Jing, Binghua, Xiao, Beibei, Ao, Zhimin
• Format: Article
• Language: English
• Subjects: Coal-fired power plants; H2O and SO2 tolerance; Incomplete combustion; NO reduction; Synergetic removing
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/j.fuel.2023.129262

NO and CO, as common pollutants in coal-fired power plants, can be directly reduced to N2 and CO2 molecules during the incomplete combustion process on a double atomic catalyst (DAC, Si-dimer doped C2N monolayer) without any reversible possibility at room temperature and/or practical temperature (600 K). [Display omitted] •Green and low-cost catalysts (Si2/C2N) was designed for NO reduction by CO.•Si2/C2N possesses high selectivity for NO and high catalytic activity with outstanding H2O/SO2 tolerance.•The coupling effect of the Si-dimer and C2N monolayer not only result in charge redistribution of Si-DAC systems, but also provide a flexible active site for the synergetic removal of NO and CO.•An efficient approach of the proper disposal of industrial exhaust during the incomplete combustion process was offered. Designing a highly effective catalyst for purification NOx emissions during the incomplete combustion process in coal-fired power plants is a valuable yet challenging task. The presence of H2O and SO2 during the NOx reduction process for flue gas treatment in coal-fired power plants is a major concern because it can lead to catalyst deactivation due to the deposition of ammonium sulfate. In this work, we propose a novel method for removing NO and CO without the traditional NH3 injection (2NO + 2CO = N2 + 2CO2) by utilizing density functional theory (DFT) calculations. Specifically, we designed metal-free single and double atomic catalysts named MFn/C2N and demonstrated that the Si-DAC (Si2/C2N) system has the highest activity for NO reduction, with outstanding resistance to deactivation from H2O and tolerance to SO2. Our findings show that Si-DAC has the best catalytic performance for NO reduction, with an extremely low energy barrier of 0.28 eV, suggesting that Si-DAC is the most effective among the reported computational results for NO removal. Overall, this work could pave the way towards designing catalytic systems with excellent activity and stability for reactions beyond NOx reduction.