Interactions between atomically dispersed copper and phosphorous species are key for the hydrochlorination of acetylene

Copper-based catalysts are widely investigated for the industrially important hydrochlorination of acetylene (PVC production), whereby phosphorus-doped carbon supports have been found to improve the catalyst's properties. Here the interaction between the P-C bond and atomically dispersed Cu2+ species is clarified and the reaction path of C2H2 and HCl revealed. Vinyl chloride, the monomer of polyvinyl chloride (PVC), is industrially synthesized via acetylene hydrochlorination. Thereby, easy to sublimate but toxic mercury chloride catalysts are widely used. It is imperative to find environmentally friendly non-mercury catalysts to promote the green production of PVC. Low-cost copper-based catalysts are promising candidates. In this study, phosphorus-doped Cu-based catalysts are prepared. It is shown that the type of phosphorus configuration and the distribution on the surface of the carrier can be adjusted by changing the calcination temperature. Among the different phosphorus species, the formed P-C bond plays a key role. The coordination structure formed by the interaction between P-C bonds and atomically dispersed Cu2+ species results in effective and stable active sites. Insights on how P-C bonds activate the substrate may provide ideas for the design and optimization of phosphorus-doped catalysts for acetylene hydrochlorination.

Automated summary

Phosphorus-doped copper-based catalysts show excellent performance in acetylene hydrochlorination, and the interaction between P-C bonds and copper ions plays a crucial role in the catalyst's activity.