Influence of Catalyst Preparation Techniques on the Properties of the Cr-Mg Catalysts for Tetrachloroethylene Hydrofluorination
The effect of the chromium-magnesium precursor preparation techniques (mixing, co-precipitation, precipitation) on
physicochemical (the BET surface area, the total pore volume, the mean pore diameter) and catalysts activity in the gas-phase hydrofluorination of perchloroethylene to pentafluoroethane was studied. It was obtained, that more active catalyst was prepared by wet mixing of the solid carrier MgF2 with a solution of CrCl3. The precursor contained 6.1% chromium, and the BET specific surface area was equal to 60 m2/g. Kinetic regularities have been studied for the most active catalyst. Based on the experimental data, the pathway of perchloroethylene fluorination with HF over a 6.1% chromium–magnesium oxide catalyst was identified. The process involves several consecutive reactions for the formation of main fluorination products and parallel reactions for the formation of by-products.