Atomic Cu-N-P-C Active Complex with Integrated Oxidation and Chlorination for Improved Ethylene Oxychlorination

Area of Science:

• Catalysis
• Materials Science
• Chemical Engineering

Background:

• Designing efficient single-atom catalysts (SACs) requires precise control over the central metal's chemical environment.
• Nitrogen-doped carbon (NC) supports are commonly used for dispersing single metal atoms.

Purpose of the Study:

• To investigate the effect of introducing a phosphorus-containing moiety (Cu-P) into a copper-nitrogen-carbon (Cu-NC) single-atom catalyst.
• To enhance the catalytic performance of Cu-based SACs for ethylene oxychlorination.

Main Methods:

• Synthesis of a novel Cu-P-N-C single-atom catalyst (Cu-NPC).
• Ethylene oxychlorination reaction testing under long-term conditions (>200 h).
• Experimental characterization and computational simulations to elucidate the active site structure and reaction mechanism.

Main Results:

• The Cu-NPC catalyst exhibited a fourfold increase in Cu site activity compared to the P-free Cu-NC catalyst.
• The catalyst showed 25 times higher activity than a commercial Ce-promoted CuCl2/Al2O3 catalyst.
• Excellent selectivity (≈99%) for ethylene dichloride and remarkable resistance to corrosive HCl were achieved.

Conclusions:

• Fine-tuning the chemical environment of SACs by incorporating additional heteroatoms like phosphorus is a viable strategy for catalyst design.
• The Cu-P-N-C SAC demonstrates superior catalytic performance and stability for ethylene oxychlorination.
• This approach offers inspiration for developing advanced carbon-based SACs for heterogeneous catalysis.