AS the supplier of fuel energy for highway transportation, the petroleum refiner has the problem of producing gasolines on a mass-production basis which will be satisfactory in many types of engines operated under widely different driving conditions. This problem is complicated by the complex chemical and physical characteristics, both of the raw materials with which the refiner must work and of his finished products.
This paper reviews the refiner's solution to this problem from the viewpoint of the transportation and maintenance engineer, and discusses the trends of the major characteristics of gasoline, namely, volatility, antiknock quality, sulfur content, gum content, and chemical composition. It suggests that the design of future engines will be in the direction of units of smaller size, having higher compression ratios, yielding higher power output and greater fuel economy, and requiring fuels of higher antiknock properties. It seems probable that, in the future, more emphasis will be placed on improving economy as well as on improving performance. It indicates that, although the trend has been toward more volatile fuels, apparently a leveling-off point has been reached. The importance of low gum content and good storage stability is stressed. Sulfur content is becoming less important so far as corrosion problems are concerned, and reduction in sulfur is now largely a question of the economics of producing high-octane fuels.
The paper also describes the composition of modern fuels and the new refining methods of polymerization, catalytic cracking, catalytic reforming, and alkylation.