GB790329A - Hydroforming process for naphthas - Google Patents

Abstract

Naphthas are hydroformed using a fluidized catalyst comprising a platinum group metal, at elevated temperature, a pressure of 0-200 p.s.i.g. and a hydrogen feed rate of 50-2000 cu. ft./barrel of oil. A portion of spent catalyst is continuously withdrawn and regenerated, to remove carbonaceous material, by contacting with an oxygen-containing gas at elevated temperature; the activity of the regenerated catalyst is increased by contacting with chlorine or a chlorine-containing gas, e.g. a gas containing 1 per cent chlorine and 99 per cent air. The hydroforming temperature may be 800-975 DEG F. Hot shot, e.g. mullite, may be used to provide part of the heat of reaction. The catalyst may contain 0.5-1.5 per cent platinum carried on active alumina, e.g. eta alumina, and may also contain a minor percentage of silica and chlorine; a palladium catalyst is also referred to. Specification 754,041 is referred to.ALSO:<PICT:0790329/III/1> In the hydroforming of naphthas using a fluidized catalyst comprising a platinum group metal (see Group IV (b)), a portion of spent catalyst is continuously withdrawn and regenerated, to remove carbonaceous material, by contacting with an oxygen-containing gas at elevated temperature; the activity of the regenerated catalyst is increased by contacting with chlorine or a chlorine-containing gas, e.g. a gas containing 1 per cent chlorine and 99 per cent air. The catalyst may contain 0.5-1.5 per cent platinum carried on active alumina, e.g. eta alumina, and may also contain a minor percentage of silica and chlorine; a palladium catalyst is also referred to. The regeneration may be carried out at 900-01200 DEG F. and 0-200 p.s.i.g. In the process described in Fig. 1, recycle gas and naphtha is contacted in reactor 1 with a bed of fluidized catalyst C and spent catalyst passed via line 35 to stripper 36 where it is stripped with steam. The catalyst is then transported in suspension in air via line 22 to the regenerator 2 where it exists as a fluidized bed; the dilute phase suspension of solids in gasiform material is forced through one or more gassolids separators to remove entrained catalyst which is returned to the bed of catalyst C1 through one or more dip pipes d. Regenerated catalyst, together with some shot (e.g. mullite) from the reactor which is used to control the regenerator temperature, then flows into lower portion 31 of the regenerator and is treated with air admitted through pipe 32. Additional chlorine or chlorine-containing gas may be added through line 33 to compensate for associated chlorine lost from the catalyst throughout the process. Hot shot used in the reactor to supply the heat of reaction is freed of catalyst and gases by stripping, in zones 37 and 38, with recycle gases and steam respectively; part of the pure shot is passed to the regenerator, as described above, and the major part passed to the burner vessel 3, where it is formed into a fluidized bed. Heated shot is returned to reactor 1 by pipe 39. Specification 754,041 is referred to.