Chemical Research in Chinese Universities ›› 2026, Vol. 42 ›› Issue (3): 938-947.doi: 10.1007/s40242-026-5310-2

• Research Articles • Previous Articles     Next Articles

Seed-assisted Template Control of ZSM-5 Structure for Mitigating Propylene Emissions over Cu/ZSM-5 Catalysts During Cold Start

WANG Rong1, MA Yirong1, LI Wenlin1, ZHANG Xin2, CHENG Jiale1, BAI Hao1, ZHENG Jiajun1, YU Feng1, FAN Binbin1, LI Ruifeng1   

  1. 1. College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan, 030024, P. R. China;
    2. China Automotive Technology and Research Center, Tianjin, 300300, P. R. China
  • Received:2025-12-29 Accepted:2026-02-11 Published:2026-06-02
  • Contact: LI Wenlin,E-mail:liwenlin@tyut.edu.cn;ZHANG Xin,E-mail:zhangxin@catarc.ac.cn;LI Ruifeng,E-mail:rfli@tyut.edu.cn E-mail:liwenlin@tyut.edu.cn;zhangxin@catarc.ac.cn;rfli@tyut.edu.cn
  • Supported by:
    This work was supported by the Project of China Automotive Technology and Research Center (No. CATARC-Z-2023-01322HC) and the National Natural Science Foundation of China (No. U21B20100).

Abstract: Cu/zeolite catalysts have attracted considerable attention for cold-start applications; however, their efficiency in propylene adsorption remains limited. To address this challenge, Cu/ZSM-5 catalysts with enhanced metal-support interactions were successfully constructed via a seed-assisted, template-mediated synthesis method, leading to improved propylene capture and oxidation efficiency. The catalysts were systematically characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR), N2 adsorption-desorption, scanning electron microscope (SEM), transmission electron microscope (TEM), NH3-TPD, X-ray photoelectron spectroscope (XPS), and in situ infrared spectroscopy to investigate the influence of acid site density and metal-support interactions on propylene adsorption behavior. The results demonstrated that Cu@ZSM-5 catalysts synthesized with different structure-directing agents exhibited distinct acidity profiles and varying strengths of metal-support interaction. Among them, the Cu@ZSM-5-130 sample prepared using the TPAOH template showed a high specific surface area (474 m2/g) and a more optimal acidity balance. It was found that an excessive density of strong acid sites can be detrimental to propylene adsorption and oxidation. The intimately associated Cu species within the zeolite matrix facilitated selective adsorption of hydrocarbons, particularly propylene. In situ infrared spectroscopy further revealed a temperature-dependent oxidation pathway of propylene over the Cu@ZSM-5-TPAOH-130 catalyst, starting with epoxide formation at low temperatures, progressing to partial oxidation products (e.g., acrolein) at intermediate temperatures, and ultimately yielding complete oxidation products, such as CO2 and H2O at higher temperatures.

Key words: ZSM-5 zeolite, Catalytic oxidation of propylene, Reaction mechanism, Acidity