CATALYSTS FOR THE CONTROL OF AUTOMOTIVE COLD START EMISSIONS

AUTOMOTIVE CATALYTIC CONVERTERS ARE QUITE EFFICIENT ONCE THEY REACH OPERATING TEMPERATURE, TYPICALLY DESTROYING OVER 98% OF THE INCOMING HYDROCARBONS (HCS) AND CARBON MONOXIDE (CO). HOWEVER, UP TO 80% OF THE EMISSIONS DURING THE FEDERAL TEST PROCEDURE OCCUR DURING THE FIRST FEW MINUTES WHEN THE ENGINE IS RUNNING RICH, THE OXYGEN SENSOR IS NOT YET OPERATIONAL, AND THE CATALYTIC CONVERTER HAS NOT REACHED ITS LIGHT-OFF TEMPERATURE. THUS, TO SIGNIFICANTLY REDUCE AUTOMOTIVE EMISSIONS OF HCS AND CO, A METHOD MUST BE FOUND WHICH WILL REDUCE THE EMISSIONS DURING THE COLD START PERIOD. TDA HAS DEVELOPED A NEW FORM OF BASE METAL OXIDE CATALYST WHICH HAS VERY HIGH ACTIVITY AT LOW TEMPERATURES (THESE CATALYSTS CAN COMPLETELY OXIDIZE CO AT -70 DEGREES CENTIGRADE, AND BE SIGNIFICANTLY MORE ACTIVE THAN PLATINUM FOR HC OXIDATION), AND WHOSE ACTIVITY IS NOT INHIBITED BY THE PRESENCE OF WATER. IN THE PHASE I PROJECT, TDA WILL USE THE BEST OF THE CATALYSTS DEVELOPED TO DATE, TEST THEIR ACTIVITY IN THE LABORATORY UNDER CONDITIONS WHICH ARE REPRESENTATIVE OF THE AUTOMOTIVE COLD START APPLICATION, PREPARE THE CATALYST IN PELLET FORM, PREPARE A PACKED BED CATALYTIC CONVERTER, AND TEST THE EFFECT OF THE CONVERTER ON THE START-UP EMISSIONS OF A 1984 VOLKSWAGEN JETTA.