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The catalytic decomposition of dichlorodifluoromethane(CFC 12) in the presence of water vapour has been carried out on WO 3/Al 2O 3 prepared by impregnating Al(OH) 3 with aqueous ammonium metatungstate followed by drying and calcining at 700 ℃ in air. On WO 3/Al 2O 3 CFC 12 was decomposed completely at 305 ℃, while on simple Al 2O 3 it needed 370 ℃; WO 3 had only a poor activity. NH 3 TPD results showed that this enhancement in activity can be explained in terms of the great acidity of WO 3/Al 2O 3. No by product was detected during decomposition of CFC 12 on WO 3/Al 2O 3, but on unmodified Al 2O 3 CFC 13 was found to be amounted to 4%. The CFC 12 conversion over WO 3/Al 2O 3 at 295 ℃ decreased from 97% to 90% in first 8 h and then took a steady value.
The catalytic decomposition of dichlorodifluoromethane (CFC 12) in the presence of water vapor has been out on WO 3 / Al 2 O 3 prepared by impregnating Al (OH) 3 with aqueous ammonium metatungstate followed by drying and calcining at 700 ° C in air. On WO 3 / Al 2 O 3 CFC 12 was decomposed completely at 305 ° C while on simple Al 2O 3 it needed 370 ° C .; WO 3 had only a poor activity. NH 3 TPD results showed that this enhancement in activity can be explained in terms of the great acidity of WO 3 / Al 2 O 3. No by product was detected during decomposition of CFC 12 on WO 3 / Al 2 O 3, but on unmodified Al 2 O 3 CFC 13 was found to be reduced to 4%. The CFC 12 conversion over WO 3 / Al 2 O 3 at 295 ° C decreased from 97% to 90% in first 8 h and then took a steady value.