Gasoline continued octane improver

The octane number of gasolines obtained with the WS2 catalyst was somewhat low. The search for catalysts continued, therefore, with two objectives. The first was the development of a catalyst of the WS2 type with decreased hydrogenating activity and increased ability to produce branched-chain hydrocarbons. The second was the development of improved catalysts for the production of highly aromatic gasolines, that is, catalysts that give higher conversion and lower formation of gaseous hydrocarbons than those of the Mo-Zn-Mg type. 

As time, passes and the petroleum industry and society develops, the demand for refinery products skyrockets, and product specifications continually tighten. New processes are developed to improve gasoline octane. Petrochemical... 

The development of ultrastable Y-zeolite catalyst led to the production of gasoline with higher olefin content and increased octane niunber. However, the need for improved catalysts continued because the zeohte was not sufficiently stable and the motor octane number did not rise as much as the research octane number. As discovered previously with other zeolites in the 1960 s, partial exchange of USY-zeolite with rare earth (REUSY) gave better stability as well as activity and provided more branched hydrocarbons and aromatics. Both motor octane number and gasoline production could thus be increased. 

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