| abstract |
A combination process for upgrading hydrocarbon fractions obtained from raw shale oil, oil products of coal processing and select fractions of crude oils comprising sulfur, nitrogen and metal contaminants to produce jet fuel product fractions such as JP4, JP5, JP8 and other turbine-type fuel materials provided. The combination of integrated processing steps involving hydrotreating, acid extraction of basic nitrogen compounds and hydrofining thereof to produce a feed composition suitable for catalytic reforming in the absence of significant hydrocracking whereby jet fuel boiling range material is produced significantly reduces by the combination the hydrogen requirements of the process. A further significant contribution to the combination operation resides in the utilization of a catalytic cracking operation of restricted severity to particularly convert high-boiling portions of the hydrocarbon feed fractions to product boiling in the jet fuel boiling range desired before acid extraction of basic nitrogen compounds and further refining thereof as above provided by hydrotreating, reforming and hydrofining of the select product of the reforming operation. Thus, the combination operation of the invention substantially maximizes the yield of desired jet fuel products under hydrogenating conditions particularly conserving the consumption of hydrogen. |