Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, School of Energy and Environment, Southeast University, Nanjing, 210096, Jiangsu, PR China.
School of Chemical Engineering, Nanjing University of Science and Technology, Nanjing, 210094, PR China.
Chemosphere. 2023 Jul;329:138613. doi: 10.1016/j.chemosphere.2023.138613. Epub 2023 Apr 6.
The synergistic degradation of VOCs and NO that were emitted from the incineration of municipal and medical wastes by a single catalyst is challenging, due to the poor activity at low temperatures, and the SO poisoning on the active sites. Herein, N-doped TiO (N-TiO) was used as the support for designing a highly efficient and stable catalyst system for CB/NO synergistic degradation even in the presence of SO. The prepared SbPdV/N-TiO catalyst, which presented excellent activity and tolerance to SO in the CBCO + SCR process, was investigated by a series of characterizations (such as XRD, TPD, XPS, H-TPR and so on) as well as DFT calculations. The electronic structure of the catalyst was effectively modulated after N doping, resulting in effective charge flow between the catalyst surface and gas molecules. More importantly, the adsorption and deposition of sulfur species and reaction transient intermediates on active centers were restrained, while a new N adsorption center for NO was provided. Abundant adsorption centers and superior redox properties ensured smooth CB/NO synergistic degradation. The removal of CB mainly follows the L-H mechanism, while NO elimination follows both E-R and L-H mechanisms. As a result, N doping provides a new approach to develop more advanced anti-SO poisoning CB/NO synergistic catalytic removal systems for extensive applications.
协同降解垃圾焚烧过程中产生的挥发性有机化合物(VOCs)和氮氧化物(NO)具有挑战性,因为单种催化剂在低温下活性较差,且活性位易被 SO 中毒。在此,我们使用 N 掺杂 TiO2(N-TiO)作为载体,设计了一种高效且稳定的催化剂体系,即使在 SO 存在的情况下,也能实现 CB/NO 的协同降解。通过一系列表征(如 XRD、TPD、XPS、H-TPR 等)和 DFT 计算,对具有优异 CBCO+SCR 活性和抗 SO 性能的 SbPdV/N-TiO 催化剂进行了研究。N 掺杂后,催化剂的电子结构得到了有效调节,从而促进了催化剂表面与气体分子之间的有效电荷转移。更重要的是,抑制了硫物种和反应瞬态中间产物在活性中心上的吸附和沉积,同时提供了新的用于吸附 NO 的 N 吸附中心。丰富的吸附中心和优越的氧化还原性能确保了 CB/NO 协同降解的顺利进行。CB 的去除主要遵循 L-H 机制,而 NO 的消除则遵循 E-R 和 L-H 两种机制。因此,N 掺杂为开发更先进的抗 SO 中毒 CB/NO 协同催化去除系统提供了新途径,具有广泛的应用前景。