Oxidative gas purification over mixt. of cobalt oxide - and Gp. IIIA metal oxide or acidic or amphoteric and basic oxides

摘要

Oxidn. of cpds. (I) present in small amts. in a gas is achieved by passing the gas over Co3O4 and gp. IIIA, i.e. Sc, Y and/or lanthanide oxide(s) or Ca3O4 on a carrier combination of involatile acidic and/or amphoteric oxide(s) and basic oxide(s). Process is useful for oxidising CO, H2, hydrocarbons, oxidised hydrocarbons, NH3 and amines, esp. in waste gases from painting, enamelling, printing and food processes and from chemical processes, e.g. phthalic anhydride mfr. and polymer degassing operations. O2 is present and the compsn. acts as catalyst. The (I) content is 100 ppm V/V to 2 vol. %. The compsn. contains 5-15 vol. % gp. IIIA metal oxide(s). E.g. 95.9% CH4 was removed from air contg. 1 vol. % CH4 using pellets of Co3O4 and CeO2 in 92:8 wt. ratio at initially 350 degrees C.