Active carbon supported TiO2–AuCl3/AC catalyst with excellent stability for acetylene hydrochlorination reaction

• TiO2–AuCl3 catalyst shows high stability for acetylene hydrochlorination reaction.
• Presence of TiO2 species partly inhibit the reduction of Au3+ to metallic Au0.
• Adsorption of HCl is strengthened due to the interaction between Au and TiO2.

In this paper, TiO2 is added to synthesize TiO2–AuCl3/AC (activated carbon) catalyst with active carbon as support, and catalytic performance of the obtained TiO2–AuCl3/AC catalyst is applied in acetylene hydrochlorination reaction. The addition of TiO2 species significantly enhances the stability of AuCl3/AC catalyst. Transmission electron microscope characterization displays the presence of anatase TiO2 phase in TiO2–AuCl3/AC catalyst. X-ray diffraction and temperature programmed reduction analysis demonstrate that the addition of TiO2 species partly inhibits the reduction of Au3+ to Au0 in acetylene hydrochlorination process. TiO2 species in TiO2–AuCl3/AC catalyst strengthens the adsorption of hydrogen chloride reactant in acetylene hydrochlorination reaction, which is attributed to the strong interaction between Au3+ active site and TiO2 species.