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Gasoline engine oils contain a variety of additives including phosphorous-based compounds, for maintaining their characteristics. During the life of the vehicle, oil is consumed via piston ring blowby or leakage from valve stem guides. Phosphorous compounds from the consumed oil end up being deposited on the three way conversion catalysts resulting in a degradation of the conversion efficiencies of all three pollutants, hydrocarbons, carbon monoxide and nitrogen oxides. To simulate this deterioration in performance, an accelerated aging cycle has been developed which replicates the effect of the interaction between the phosphorous species and the washcoat components. This paper describes the poison aging protocol and the effect of aging temperature, poison level and duration of aging. In this paper, we will we also discuss some of the catalyst deactivation mechanisms and methods to simulate them using dynamometer-mounted engines.

Gasoline engine oils contain a variety of additives including phosphorous-based compounds, for maintaining their characteristics. During the life of the vehicle, oil is consumed via piston ring blowby or leakage from valve stem guides. Phosphorous compounds from the consumed oil end up being deposited on the three way conversion catalysts resulting in a degradation of the conversion efficiencies of all three pollutants, hydrocarbons, carbon monoxide and nitrogen oxides. To simulate this deterioration in performance, an accelerated aging cycle has been developed which replicates the effect of the interaction between the phosphorous species and the washcoat components. This paper describes the poison aging protocol and the effect of aging temperature, poison level and duration of aging. In this paper, we will we also discuss some of the catalyst deactivation mechanisms and methods to simulate them using dynamometer-mounted engines.

The Federal Test Procedure (FTP) test contains an initial period, prior to the catalyst becoming fully activated, during which hydrocarbons escape the vehicle. These hydrocarbons constitute 60-80% of the total emitted over the entire FTP test. To meet future emission levels mandated by the California Air Resources Board, alternate technologies must be created that deal effectively with these cold start hydrocarbons. This paper describes an adsorbent bed/catalyst system that can trap approximately 70% of the available nonmethane hydrocarbons over the first two minutes of the FTP test. Importantly, the trap does not require bypass valves because of a unique heat exchange approach to catalytically consuming the trapped hydrocarbons, and because the trapping materials are unaffected by engine exhaust temperatures below 800°C. Experiments with a prototype system demonstrate that LEV emissions are possible.