Two soluble phthalocyanines, cobalt(II)- and iron(III)-octacarboxyphthalocyanines have been examined as catalysts for the oxidation of methanethiol and hydrogen sulphide. Under similar conditions, the cobalt phthalocyanine exhibited higher catalytic activity than the iron compound. On the other hand it was found that when the two catalysts were employed together in equal molar quantities a synergistic effect was observed. For its practical application to the removal of odours caused by methanethiol and hydrogen sulphide, the two metallophthalocyanines were used to dye viscose fibre, pretreated with a cationic agent producing a novel air-purifying material. The dyed fabric was highly effective at eliminating odours caused by these two compounds.