Method of treating exhaust gases

Claim 1

IN A PROCESS OF CATALYTICALLY EFFECTING SUBSTANTIALLY COMPLETE COMBUSTION OF EXHAUST GASES FROM INTERNAL COMBUSTION ENGINES, THE STEP WHICH COMPRISES PASSING THE EXHAUST GASES WITH THE ADDITION OF SECONDARY AIR AT THE REACTION TEMPERATURE OVER AND THROUGH A CATALYST BED CONSISTING OF EXTRUDED CATALYST BODIES OBTAINED BY PROCESS STEPS WHICH CONSIST IN (A) ADDING AMMONIA TO AN ALUMINUM SALT SOLUTION TO PRECIPITATE ALUMINUM HYDROXIDE GEL, (B) DRYING SAID GEL, (C) GRINDING SAID DRIED GEL TO A PARTICLE SIZE SMALLER THAN 100 U, (D) MIXING SAID DRIED AND GROUND GEL WITH DILUTE ACETIC IN AN AMOUNT SUFFICIENT TO PEPTIZE THE DRIED GEL AND TO PRODUCE A MIXTURE OF A CONSISTENCY SUITABLE FOR EXTRUSION, (E) EXTRUDING SAID MIXTURE TO CATALYST CARRIER BODIES, (F) DRYING SAID CARRIER BODIES, (G) CALCINING SAID DRIED CARRIER BODIES AT A TEMPERATURE BETWEEN ABOUT 900*C. AND ABOUT 1300*C, (H) IMPREGNATING SAID CALCINED CARRIER BODIES WITH METAL COMPOUNDS CATALYTICALLY EFFECTING COMBUSTION OF EXHAUST GASES, (I) DRYING THE IMPREGNATED CATALYST BODIES, AND (J) CALCINING THE DRIED BODIES AT A TEMPERATURE OF AT LEAST 800*C.