Reactive and deactivation mechanisms of acetylene dimerization on CuCl2/AC catalyst

Gas-solid acetylene dimerization has provided a facile and effective way to product MVA under mild conditions, whereas the copper-based catalysts using cuprous chloride as precursor are generally not regarded as ideal candidates, owing to its good ability for reaction with acetylene to produce explosive cuprous acetylide, and needs to help with other solvents and cosolvents for above process. Herein, we proposed a CuCl2/AC catalyst with CuCl2·H2O as the precursor. The reaction and deactivation mechanism of CuCl2/AC catalyst were investigated through experimental characterization and DFT calculation. Theoretical calculations revealed that the Cu(II) reduction, Cl dissociation (TS-1) was the rate-limiting step in CuCl2/AC catalyst for acetylene dimerization reaction, and the acetylene dimerization reaction prefers to the main-reaction path of generating MVA. Moreover, ICP analysis indicated that catalyst deactivation during acetylene dimerization could be attributed to active component loss. This work provides new theoretical insights into gas-solid acetylene dimerization.