Patent GB-742405-A (GB)
Title: Improved fluidized hydroforming process
IPC: C10G35/14
Filed: 1953-03-06
Abstract: Naphthenic petroleum hydrocarbons boiling in the gasoline range are hydroformed in a dense fluidized bed of hydroforming catalyst in a reaction zone by a process of the type wherein hydroforming catalyst is withdrawn from the reaction zone to a regenerator, the carbon content is reduced, and is then returned to the reaction zone, characterized in that a dense fluidized bed of the freshly regenerated catalyst is stripped in a stripping zone with a hot inert gas, such as air, flue gas or nitrogen, containing less than 0.2 pounds of water per 1000 standard cubic feet, and preferably with a velocity of 0.5 to 1.0 ft. per second at 200 p.s.i., before the regenerated catalyst is returned to the reaction zone.  The stripped, regenerated catalyst may be cooled to reactor temperature, e.g. by indirect heat exchange with dry stripping gas, recycle gas and fresh naphtha feed; heat exchange with the dense bed of catalyst in the reactor, or with a stream of recycle reactor catalyst, is also referred to; the cooled catalyst may be contacted with the naphtha feed before being returned to the reaction zone.  The stripping gas may be dried by compressing to 200 lbs. p.s.i. and cooling to 100 DEG F., or by passing through a suitable dehydrating agent.  The feedstock is preheated to 800-1000 DEG  F., partly by indirect heat exchange with regenerated catalyst.  Recycle gas containing 50-70 vol. per cent of hydrogen is preheated to 1150-1250 DEG  F. and circulated at 1000 to 8000 cubic ft. per bbl. of naphtha feed.  The catalyst may be a Group VI metal oxide, preferably molybdenum or chromium oxide supported on alumina or zinc spinel.  The reactor is operated at 850-925 DEG  F. and 50 to 500 lbs. p.s.i. and the regenerator at 1150-1250 DEG  F.  The regenerated catalyst to oil ratio is preferably 0.5 to 1.5 and the space velocity 1.5 to 0.15 wt/hr/wt.  Specification 733,799 is referred to.ALSO:<PICT:0742405/III/1> Naphthenic petroleum hydrocarbons boiling in the gasoline range are hydroformed in a dense fluidized bed of catalyst 15 in a reactor 10, the spent catalyst is continuously discharged into stripper 20, or a corresponding internal stripper (not shown), wherein it is stripped with steam and is then conveyed by a stream of air to regenerator 30, wherein the carbon content is reduced, and is then returned to the reaction zone, characterized in that a dense fluidized bed of the freshly regenerated catalyst is stripped in a stripping zone 42 with a hot inert gas such as air, flue gas or nitrogen, containing less than 0.2 pounds of water per 1000 standard cubic feet, and preferably with a velocity of 0.5 to 1.0 ft. per second at 200 p.s.i.g., before the regenerated catalyst is returned to the reaction zone.  The stripped, regenerated catalyst may be passed through cooler 46 in indirect heat-exchange with dry stripping gas passing through coil 40, with recycle gas through coil 49 and with fresh naphtha feed through coil 53; heat-exchange with the dense bed of catalyst reactor 10 or with a stream of recycle reactor catalyst is also referred to; the solid catalyst is contacted with naphtha feed in inlet line 11, before being returned to the reaction zone.  The stripping gas may be dried by compressing to 200 lbs. p.s.i.g. and cooling to 100 DEG F. or by passing through a suitable dehydrating agent. Specification 733,799, [Group IV(b)], is referred to.