Vitamin C‐Assisted Synthesis of Novel Cu‐SSZ‐13 Zeolite and Its High‐Efficiency Performance in Diesel Vehicle NO _x Exhaust Purification

ABSTRACT Diesel vehicle‐derived NO x is a major pollutant, and NH 3 ‐SCR with Cu‐SSZ‐13 is the mainstream abatement technology. In this study, vitamin C (Vc) was used as a crystal growth regulator to successfully synthesize Cu‐SSZ‐13‐Vc0.3 via the hydrothermal method. Experimental results demonstrate that the introduction of Vc significantly optimizes the performance of the zeolite: It broadens the active temperature window and simultaneously enhances hydrothermal stability and resistance to sulfur poisoning. Compared with the conventional Cu‐SSZ‐13, the Vc‐assisted synthesized Cu‐SSZ‐13‐Vc0.3 sample possesses a larger micropore volume and specific surface area, which are favorable for the loading of active Cu 2+ ions and the structural stability of the zeolite. The Cu‐SSZ‐13‐Vc0.3 sample forms a greater number of tetracoordinated framework Al species and isolated Cu 2+ ion species; meanwhile, the number of acidic sites increases significantly. These factors may collectively contribute to the enhanced catalytic activity of Cu‐SSZ‐13‐Vc0.3, as well as its improved resistance to hydrothermal aging and sulfur poisoning. Specifically, after hydrothermal aging, it still maintains excellent structural stability and catalytic activity, with a NO conversion rate of 98% (at 215 °C) and outstanding hydrothermal stability (a T 90 temperature window of 200–425 °C). Consequently, the Vc‐assisted synthesis of Cu‐SSZ‐13‐Vc0.3 zeolite holds broad application prospects in the field of diesel engine exhaust denitrification.