The national concern over air quality and the understanding of the role of the internal combustion engine powered passenger car as a contributor of atmospheric pollutants has imposed new design criteria upon both the automobile manufacturer and the petroleum refiner. For the passenger car engine builder these criteria have been specified by the emission standards required by the Clean Air Amendments of 1970. With certain exceptions, gasolines for these low-emitting passenger cars have not yet been specified nor have their required quality and performance characteristics been clearly spelled out. This paper attempts to judge the influence of emission control requirements on future gasoline quality. Lead anti-knocks, hydrocarbon compositions and gross physical properties are among the factors considered and an effort is made to quantify the effects of changes in these characteristics on emissions and to estimate their impact on the industry. It is concluded that future automotive fuels, i.e., fuels that will be produced for future emission controlled vehicles, will be a blend of liquid hydrocarbons, free of lead alkyl anti-knocks and other catalyst poisons, and with hydrocarbon composition and volatility modestly adjusted to provide optimum emissions control at lowest overall system cost.
