(EP830200-A1)      A catalyst to oxidise oxygen-contg. organic cpds. to CO2 and water comprises perovskite on a metal oxide support.    Also claimed is a method of reducing the amt. of volatile oxygen-contg. organic cpd. in waste gas by oxidn. to form CO2 and water.    Pref. the metal oxide support is a stabilized metal oxide, or one or more of aluminium oxide, magnesium oxide, titanium oxide and zirconium oxide, or alumina. The stabilized metal oxide support comprises metal oxide having a layer of an oxide of a different metal comprising Mg, Fe, Co, Ni, Mn, Zn, Ti, Cu, Cr, La, Ba, Ca, Sr or Ag on the surface thereof. The formula of the perovskite is La1-xAxYO3, where x is 0-1, A is Ag or Mg and Y is Mn or Fe, and x is esp. 0.1-0.75.    Pref. the organic cpd. is ethanol and oxidn. is effected by contacting the gas with the perovskite catalyst as described above. Oxidn. is at up to 550F max..    USE -   The catalyst is used in treating waste gas produced from fermentation, baking and brewing.    (US5789339-A)      A catalyst to oxidise oxygen-contg. organic cpds. to CO2 and water comprises perovskite on a metal oxide support.    Also claimed is a method of reducing the amt. of volatile oxygen-contg. organic cpd. in waste gas by oxidn. to form CO2 and water.    Pref. the metal oxide support is a stabilized metal oxide, or one or more of aluminium oxide, magnesium oxide, titanium oxide and zirconium oxide, or alumina. The stabilized metal oxide support comprises metal oxide having a layer of an oxide of a different metal comprising Mg, Fe, Co, Ni, Mn, Zn, Ti, Cu, Cr, La, Ba, Ca, Sr or Ag on the surface thereof. The formula of the perovskite is La1-xAxYO3, where x is 0-1, A is Ag or Mg and Y is Mn or Fe, and x is esp. 0.1-0.75.    Pref. the organic cpd. is ethanol and oxidn. is effected by contacting the gas with the perovskite catalyst as described above. Oxidn. is at up to 550F max..    USE -   The catalyst is used in treating waste gas produced from fermentation, baking and brewing.    (US5882616-A)      A catalyst to oxidise oxygen-contg. organic cpds. to CO2 and water comprises perovskite on a metal oxide support.    Also claimed is a method of reducing the amt. of volatile oxygen-contg. organic cpd. in waste gas by oxidn. to form CO2 and water.    Pref. the metal oxide support is a stabilized metal oxide, or one or more of aluminium oxide, magnesium oxide, titanium oxide and zirconium oxide, or alumina. The stabilized metal oxide support comprises metal oxide having a layer of an oxide of a different metal comprising Mg, Fe, Co, Ni, Mn, Zn, Ti, Cu, Cr, La, Ba, Ca, Sr or Ag on the surface thereof. The formula of the perovskite is La1-xAxYO3, where x is 0-1, A is Ag or Mg and Y is Mn or Fe, and x is esp. 0.1-0.75.    Pref. the organic cpd. is ethanol and oxidn. is effected by contacting the gas with the perovskite catalyst as described above. Oxidn. is at up to 550F max..    USE -   The catalyst is used in treating waste gas produced from fermentation, baking and brewing.