Hydrocracking isocracking process

Isocracking process a hydrocracking process for conversion of hydrocarbons which operates at relatively low temperatures and pressures in the presence of hydrogen and a catalyst to produce more valuable, lower-boiling products. 

In this paper, we will review the considerations that led to the development of modern hydrocracking and some aspects of the chemistry of hydrocracking. Also, we will briefly discuss some of the advances in hydrocracking during the 23 years since the Isocracking process was announced. 

In 1961, hydrocracking was introduced to convert gas oil into naphthene-rich heavy naphtha, which is a superb feed for a catalytic reformer. The first unit used the Isocracking process developed by Standard Oil of California (now Chevron Texaco). 

Superficially the Oryx GTL refinery design has much in common with the SMDS process, but there are important differences. There is no separate hydrotreater, which limits production of chemicals, such as waxes. The hydrocracker employs the Chevron Isocracking technology, which is based on a sulfided supported base-metal catalyst that was designed for crude oil conversion. The operating conditions of the hydrocracker are also more severe (>350°C, 7 MPa) than those required by the SMDS process (300-350°C, 3-5 MPa). Only intermediate products are produced (Table 18.13),5 with the naphtha slated as cracker feed and the distillate as blending component for diesel fuel. 

Isocracking A hydrocracking process developed and licensed by Chevron Research Company. The catalyst is nickel or cobalt sulfide on an aluminosilicate. First commercialized in 1962 more than 45 units had been built by 1994. See also Isomax. 

Bridge, A.G. (1997) Chevron isocracking-hydrocracking for superior fuels and lubes production, in Handbook of Petroleum Refining Processes, 2nd edn (ed. R.A. Myers), McGraw-Hill,... 

Isocracking A hydrocracking process, developed by Chevron and now licensed by Chevron Lummus Global. The catalyst contains a mixture of hydrous oxides for cracking, plus heavy metal sulfides for hydrogenation. First commercialized in 1962 and now widely licensed worldwide. See also Isomax. 

A fortunate combination of theoretical considerations and experimental circumstances directed attention to some unusual reaction paths. This led to detailed studies of reactions of typical hydrocarbon classes. New and highly specific nonequilibrium reactions were identified. Techniques and catalysts were discovered which permitted desirable reactions of the individual hydrocarbon classes to dominate the conversion of mixtures. These studies became the basis for the commercial hydrocracking process called Isocracking and the catalysts developed for this service. The technical objectives of a low pressure, low temperature process were achieved as demonstrated... 

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