Characterization of Au species in Au/C catalysts for the hydrochlorination reaction of acetylene
نویسندگان
چکیده
A set of Au/C catalysts for the gas phase hydrochlorination of acetylene to vinyl chloride monomer were prepared using a range of strong acids as impregnating solvents and varying the preparation drying temperature. The most active catalyst is the material prepared using aqua regia as solvent with an intermediate drying temperature of 140 C. The effects of the catalyst preparation parameters on the catalytic activity are examined using XPS and TPR as analytical tools. In particular, the use of thermal reduction methods allows the determination of kinetic parameters for the reduction of Au to Au by means of H2. These data support the existence of a redox cycle between Au/Au when carbon is used as support.
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