GB1312994A - Production of jet fuel - Google Patents

Abstract

1312994 Hydrogenating and hydrocracking hydrocarbons ESSO RESEARCH & ENG CO 20 July 1970 [4 Aug 1969 (2)] 35025/70 Heading C5E Jet fuel is produced from an aromatics-containing feed, containing not more than 25 p.p.m. of sulphur by contacting with hydrogen at 200-780‹ F., 200-5000 p.s.i.g., and a space velocity of at least 0À5 v./v./hr. using a catalyst containing 0À05-30 wt. per cent of a Group VIII metal, e.g. Ni or Pt, and 0À1-2 wt. per cent fluoride composited with a refractory metal oxide, e.g. alumina, so as to convert aromatics to naphthenes. The catalyst suitably has a surface area of 250-600 sq. m./g. and its fluoride content can be maintained by the addition of HF or organic fluoride to the feed during processing. The jet fuel can be produced by (a) hydrotreating a feed, such as a virgin naphtha, highly aromatic hydrocracked feed or middle distillate suitably boiling within the range 320-550‹ F., or (b) hydrocracking feeds boiling in the range 430-850‹ F., to produce jet fuels and gasoline, suitable feeds are virgin gas oils, deasphalted oils containing 8-30 wt. per cent aromatics, catalytically cracked fractions containing 30- 70 wt. per cent aromatics, fractions from thermal, delayed and fluid cokers, shale oil, and solubilized coal. Fig. 1 (not shown) illustrates a process in which an aromatics containing feed is hydrofined at 600-850‹ F. and 800-5000 p.s.i.g. using a conventional catalyst, such as Co, Mo, Ni, W or a mixture of these on an inorganic oxide, charcoal or clay. The hydrofinate is scrubbed to remove hydrogen sulphide and then subjected to the low severity hydrocracking process of the invention and then fractionated. As shown in Fig. 2, a feed 38 is hydrofined using a conventional catalyst and then hydrocracked at 50 at 500-850‹ F. and 500-5000 p.s.i.g. using a conventional catalyst such as Pt, Pd, Ni or W on a crystalline zeolite, e.g. a platinum hydrogen faujasite. The hydrocrackate is distilled at 70 to produce a C 5 - 430‹ F. gasoline fraction and a heavier stream 54 which is passed to the low severity hydrocracking stage 60 of the invention. The hydrocracked effluent 61 is separated at 80 into a C 5 -320‹ F. gasoline fraction, a 320-550‹ F. jet fuel fraction and a recycle stream 62.