Hydrochlorination Of Acetylene Using The Novel Sic Foam With Hollow Structure Supported Au/C Catalysts

Acetylene hydrochlorination using Au/C as catalyst, is an important process to produce vinyl chloride. It is a highly exothermic and diffusion-controlled reaction with local hot spots and poor diffusion process in the fixed-bed reactor, weakening the catalytic performance of Au catalyst. The structuring of catalyst using solid SiC foam ceramic can solve the above problems through optimizing spatial distribution of Au/C, reducing the pressure drop and temperature rise. In order to further disperse Au/C, the novel SiC foam with hollow structure was manufactured to compare with solid SiC foam. The hollow foam structured catalyst has inside and outside surface, thinner catalyst coating and smaller Au particles. Thus it provides more active site accessible to the reactants and further shortens the diffusion distance, then improving the catalytic efficiency. The catalytic lifetime (acetylene conversion above 90%) of hollow SiC foam structured catalyst is 205 hours while that of solid foam is 126 hours at acetylene gaseous hourly space velocity (GHSV) of 120 h(-1). In conclusion, the better dispersion of Au/C on hollow SiC foam supported structured catalyst is the main reason for activity and stability enhancement.