Enhanced NH₃-SCR activity of Cu-SAPO-34 by regulating Si distribution via an interzeolite conversion strategy

Area of Science:

• Materials Science
• Catalysis
• Environmental Chemistry

Background:

• Selective Catalytic Reduction (SCR) is crucial for NOx emission control.
• Developing efficient and stable catalysts for NH3-SCR is an ongoing challenge.
• SAPO-34 zeolites are promising supports, but optimizing copper dispersion and active sites is key.

Purpose of the Study:

• To develop a rapid synthesis method for Cu-SAPO-34 with isolated Si.
• To investigate the relationship between catalyst structure and NH3-SCR performance.
• To achieve high NOx conversion over a wide temperature range.

Main Methods:

• Interzeolite conversion (IZC) of SAPO-37 to SAPO-34.
• Incorporation of copper into the SAPO-34 framework.
• Characterization of the synthesized Cu-SAPO-34 materials.
• Evaluation of NH3-SCR performance for NOx removal.

Main Results:

• Rapid synthesis of Cu-SAPO-34 achieved via IZC from SAPO-37.
• Isolated Si distribution and optimized Cu states were successfully obtained.
• The Cu-SAPO-34 catalyst demonstrated over 90% NO conversion from 200-600 °C.
• Effective NH3-SCR performance correlated with proper acidity and Cu status.

Conclusions:

• The IZC method is effective for synthesizing high-performance Cu-SAPO-34 catalysts.
• Isolated Si and optimized Cu states are critical for exceptional NH3-SCR activity.
• This catalyst offers a promising solution for controlling NOx emissions.