Guangxi Iron & Steel Group Co., Ltd.
School of Energy and Environment,Anhui University of Technology
School of Metallurgical Engineering, AnhuiUniversity of Technology

氮氧化物(NOx)作为主要大气污染物之一,严重影响环境安全和人类健康。 选择性催化还原法(NH3-SCR)是目前脱除 NOx最有效的治理方法,尤其是低温 SCR 脱硝技术具有非常重要的应用前景和研究意义。 研究表明 VPO/ TiO2 催化剂具有优异的低温 SCR 脱硝活性,本文通过DFT 模拟 NH3和 NO 在 V2O5和(VO) 2P2O7表面的吸附,对 VPO 催化剂的反应机理进行了微观层面上的研究。 研究表明 NH3在 V4P4O22H14团簇表面的 Brønsted 酸和 Lewis 酸都发生稳定的化学吸附,在 Brønsted 酸位点吸附更稳定,并且 NH3在催化剂表面吸附效果佳是因为 N 的 2p 轨道和O 的 2p、V 的 3d 电子轨道能发生了杂化。 NO 在 V4P4O22H14团簇表面也是化学吸附,由于电子转移量较小,显著低于 NH3的吸附能,并不能和 NH3分子产生强烈竞争,另外 NO 在 V6O20H10团簇表面的 Brønsted 酸和 Lewis 酸均发生稳定的化学吸附,且在 Brønsted 酸位点吸附更稳定。 说明了VPO/ TiO2催化剂反应机理中的 E-R 机理和 L-H 机理。

Nitrogen oxides (NOx), as one of the main atmospheric pollutants, seriously affect environ⁃mental safety and human health. Selective catalytic reduction (NH3-SCR) is the most effective treat⁃ment method for NOx removal at present, especially low-temperature SCR denitrification technology,which has very important application prospects and research significance. The research showed thatVPO/ TiO2 catalyst had excellent low-temperature SCR denitrification activity. The adsorption of NH3and NO on V2O5 and (VO) 2P2O7 surface was simulated by DFT, and the reaction mechanism of VPOcatalyst was studied at the micro level. The results showed that NH3 exhibited stable chemisorption ofBrønsted acid and Lewis acid on the surface of V4 P4 O22 H14 cluster, and the adsorption effect onBrønsted acid sites was more stable. NH3 adsorption effect on the surface of catalyst was excellent be⁃cause of the hybridization of 2p orbital of N, 2p of O, and 3d electron orbital of V. NO also showedchemisorption on the surface of V4P4O22H14 cluster. Due to the small amount of electron transfer, whichwas significantly lower than the adsorption energy of NH3, NO could not strongly compete with NH3molecule. In addition, NO showed stable chemisorption on Brønsted acid and Lewis acid on the surfaceof V6O20H10 cluster. The adsorption on Brønsted acid sites was more stable. The E-R mechanism andL-H mechanism of VPO/ TiO2 catalyst reaction mechanism were explained.

安徽省自然科学基金项目(KJ2019A0079,KJ2020A0236)

黎柳升, 徐彬, 张铭,等. DFT 模拟 VPO/ TiO2 催化剂表面 NO 和 NH3 吸附的研究[ J]. 能源环境保护,2023, 37(4): 140-148.

LI Liusheng, XU Bin, ZHANG Ming,et al. Study on adsorption of NO and NH3 on VPO/ TiO2 catalysts by DFTsimulation[J]. Energy Environmental Protection, 2023, 37(4): 140-148.