Gasoline fuel

Abstract

Total combustion and evaporative emissions from gasoline pump fuels can be controlled with total emissions no higher than those currently allowed by the addition of an evaporative factor such as RVP to the model predicting emissions, based on a number of considerations including the sensitivity of emission parameters (toxics, hydrocarbons, CO and NOx) as related to the variables in the predictive model (oxygenate content, sulfur, T90, T50, aromatics, olefins, benzene and RVP). The present pump gasolines will normally have compositions including T10 no greater than 140° F., T90 no greater than 330° F., RVP no greater than 7 psi and usually lower and sulfur no greater than 50 ppmw. Oxygenates may be eliminated, permitting T50 values to increase which is not unfavorable from the viewpoint of total emissions provided other parameters are held within specified limits. Aromatics, olefins and benzene are normally held to maximum of 35, 10 and 1 vol % respectively to achieve satisfactorily low total emissions.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application is a continuation-in-part of U.S. Ser. No. 09 / 226,409 filed Jan. 6, 1999 now abandoned which claims priority of U.S. Ser. No. 60 / 070,814 filed Jan. 8, 1998.FIELD OF THE INVENTION[0002]The present invention relates to fuels and particularly to gasoline fuels suitable for use in road vehicles. It is more particularly directed to gasoline fuels suitable for use in road vehicles as a standard pump fuel suitable to be supplied throughout the manufacturing and distribution system of the petroleum refining industry in large quantities.BACKGROUND OF THE INVENTION[0003]One of the major environmental problems confronting certain areas including major cities, in the United States and other countries is of atmospheric pollution associated with the emission of gaseous pollutants from automobiles, including both evaporative emissions and exhaust gas pollutants. This problem may be acute in major metropolitan areas such as Los Angeles, ...

AI Technical Summary

Benefits of technology

[0016]According to the present invention, pump gasolines are formulated to have total emissions (evaporative plus combustive) no higher than those which would be permissible under current regulations, specifically the CARB regulations referred to above. Although variation in the current regulations may be required in certain instances, it is believed that actual emissions (total) would be at least equivalent that is, equivalent or better, to those resulting from current fuels. The present gasolines are, of course, lead-free in accordance with current EPA regulations.

[0017]Conceptually, the present fuels can be categorized in three ways. The first group of fuels is characterized by a T50 in the range of 210 to 215° F. and with other compositional properties including low sulfur levels which confer good emission performance. The second group has an even higher T50, in the range of 215 to 220° F. and again with other compositional characteristics which confer good emissions performance. The third group has a low T50 value below about 210° F. but here, it has been found that it is possible to enlarge the volume of the gasoline pool by the use of an extended T90 about 315° F., normally from 315° F. to 330° F.

[0018]The present gasoline fuel compositions may by produced by conventional refining and blending techniques using such refinery processes as distillation, cracking, reforming and alkylation with blending of the appropriate fractions such as naphtha, FCC gasoline, reformate and alkylate.

Problems solved by technology

One of the major environmental problems confronting certain areas including major cities, in the United States and other countries is of atmospheric pollution associated with the emission of gaseous pollutants from automobiles, including both evaporative emissions and exhaust gas pollutants.

This problem may be acute in major metropolitan areas such as Los Angeles, Calif. where atmospheric conditions in combination with large numbers of automobiles create appropriate conditions for aggravated air pollution.

The composition of motor gasolines commercially sold for normal road vehicle use in certain areas of the United States is now restricted by Federal and, in some cases, by State regulations.

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