Treatment of exhaust gases

Claim 1

A PROCESS FOR EFFECTING SUBSTANTIALLY COMPLETE OXIDATION OF CARBON MONOXIDE AND HYDROCARBONS CONTAINED IN AUTOMOBILE EXHAUST GASES WHICH COMPRISES: CONTACTING SAID GASES WITH A CATALYSTIC STRUCTURE COMPRISING (A) A TUBULAR CASING; (B) METAL WOOL SUBSTRATE CONTAINED WITHIN SAID CASING; (C) AN ADHERENT FILM OF ALUMINA FORMED ON SAID SUBSTRATE AND THE INTERIOR OF SAID CASING THEREBY BONDING SAID SUBSTRATE AND SAID CASING TOGETHER IN A UNITARY STRUCTURE SAID ADHERENT FILM OF ALUMINA BEING FORMED BY (1) CONTACTING SAID SUBSTRATE AND SAID CASING WITH AN AQUEOUS SOLUTION OF AN ALKALI METAL ALUMINATE FOR A PERIOD OF TIME SUFFICIENT TO FORM AN ADHERENT FILM OF ALUMINA TRIHYDRATE ON SAID SUBSTRATE AND SAID CASING WHEREIN THE SOLUTION TEMPERATURE IS AT LEAST ROOM TEMPERATURE; (2) SUBSEQUENTLY, SEPARATING SAID SUBSTRATE AND SAID CASING WITH SAID ADHERENT FILM OF ALUMINA TRIHYDRATE FROM SAID SOLUTION, AND (3) THEN, HEATING SAID SUBSTRATE, SAID CASING AND SAID FILM OF ALUMINA TRIHYDRATE UNDER CALCINING CONDITIONS FOR SUFFICIENT TIME TO AT LEAST DEHYDRATE SAID ALUMINA TRIHYDCRATE, AND; (D) AN OXIDATION CATALYST DEPOSITED ON SAID ALUMINA AND ADHERENT THERETO.