Exhaust Gas Purification for Europe
Exhaust emissions are currently controlled without the use of catalysts in Europe; however, exhaust emission standards have been proposed which might lead to catalyst systems which differ significantly from those used in the United States and Japan . Exhaust emission standards being discussed are aimed at 90% reductions in emissions compared with 1969 levels . Koberstein et al  state that the proposed CO emission standard varies with the inertial weight of the vehicle, while the HC and NOx emissions are added together to meet a single standard. No durability schedule has yet been adopted. The emissions test method (called the ECE-test after the Economic Commission for Europe) differs from the CVS-test used in the United States, and emissions measured with the two tests cannot be directly compared. These two driving schedules are shown in Figure 23. A main difference between the European and U.S. approach to exhaust emission control is that lead-free gasoline will not be available in Europe (except perhaps in Switzerland). Accordingly catalyst systems must be developed which are compatible with lead content in the range 0.15 to 0.4 g l-1 . No catalyst schemes have been identified which can be used to meet U.S. exhaust emission standards at such high lead content.
KeywordsOxidation Catalyst Catalyst System Catalytic Converter Lead Poisoning Driving Schedule
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