Synergistic removal of NO and soot by Fe-W-Zr-ZSM-5 catalysts in a wide temperature window. (15th February 2023)

• Record Type: Journal Article
• Authors: Feng, Shuo; Zhang, Chenguang; Xing, Yuye; Li, Zhaoming; Shen, Boxiong; Wang, Fumei; Yuan, Peng; Wang, Zhuozhi; Ma, Jiao; Kong, Wenwen
• Is Part Of: Fuel. Volume 334(2023)Part 2
• Publication Date: 2023-02-15
• Subjects: NH3-SCR -- Soot oxidation -- Synergistic removal of NO and soot -- W-Zr-ZSM-5; Fuel -- Periodicals; Coal -- Periodicals; Coal; Fuel; Periodicals; 662.6
• DOI: 10.1016/j.fuel.2022.126772
• Languages: English
• ISSNs: 0016-2361

Abstract

Graphical abstract: Highlights: The W 5+ and W = O species of Fe-W-Zr-ZSM-5 and Cu-W-Zr-ZSM-5 catalysts were significantly improved by the interaction between W and Cu or Fe species. The content of chemisorbed oxygen and surface acid sites over Fe-W-Zr-ZSM-5 and Cu-W-Zr-ZSM-5 catalysts were enhanced by the W 5+ and W = O species. Fe species and chemisorbed oxygen could promote the oxidation of soot. Fe-W-Zr-ZSM-5 catalyst could achieve the synergistic catalytic removal of NO and soot at wide temperature. Abstract: Obtaining the synergistic catalytic removal of NO and soot is a highlight topic as both NO and soot are the main pollutants from diesel engine. However, synergistic catalytic removal is still very difficult because the temperature window varies with the traditional SCR catalyst of NO at narrow temperature of 300–450 ℃ and the oxidation temperature of soot at high temperature of 500–700 ℃. Therefore, based on W-Zr-ZSM-5 catalyst, a series of M-W-Zr-ZSM-5 (M = Cu, Fe or Nb) catalysts were prepared by sol–gel method to investigate the synergistic catalytic removal of NO and soot, which emitted from diesel engine at the same time. The results showed that Fe-W-Zr-ZSM-5 catalyst exhibited the best NH3 -SCR reaction activity and oxidizing performance of soot among the catalysts, with more than 90 % NO conversion in the temperature range of 320 ℃ to 580 ℃ and completely oxidization of soot in the temperature range of 432 ℃ to 543 ℃. The results of XRD, BET, XPS and Raman spectrum indicated that there was strong interaction between W and Fe, promoting the formation of W 5+ and W = O species, thereby increasing the content of chemisorbed oxygen, the amount of surface acid sites and redox capacity of the catalysts. Meanwhile, the redox capacity of Fe-W-Zr-ZSM-5 was responsible for the improvement of NH3 -SCR activity and the oxidation of soot at low temperature. Fe-W-Zr-ZSM-5 catalyst demonstrated to be a promising material to synergistic remove NO and soot.