GB602263A - Improved process for the dehydrogenation of butenes - Google Patents

Abstract

<PICT:0602263/III/1> In a process for the catalytic dehydrogenation of butenes to produce butadiene, butene, steam, and powdered catalyst are led into reactor 10 which is maintained completely full of the mixture in a dense fluidized state; the catalyst-gas mixture passes overhead to a separator 26 and the separated reaction products are quenched, for example by the introduction through line 40 of water, other vaporisable liquids, or cold catalyst; part of the separated catalyst returns direct to the reactor through line 29, and part is treated with steam in regenerator 38 (where carbonaceous material is removed by the water-gas reaction), and then passes back to the reactor through line 16. Catalyst also passes from the reactor to the regenerator via line 52. By using superheated steam for regeneration, the temperature of the catalyst is raised to 1200 DEG -1500 DEG F. in order to supply heat to the butene feed, which is brought to a temperature of 800 DEG -1000 DEG p F.; the reaction products are quenched to 500 DEG -1000 DEG F. Additional heat may be supplied to the regenerator by burning-fuel therein. Valves 22, 30 and 35 may be automatically controlled according respectively to the temperature in the reactor or regenerator, the pressure in the reactor, and the level in the separator 26. Suitable catalysts are the oxides of iron, magnesium, and copper, with or without potassium oxide. A potassium compound may be added during regeneration to replace that lost during the process. Specification 557,624 is referred to.ALSO:<PICT:0602263/IV(b)/1> In a process for the catalytic dehydrogenation of butenes to produce butadiene, butenes, steam, and powdered catalyst are led into reactor 10 which is maintained completely full of the mixture in a dense fluidized state; the catalyst-gas mixture passes overhead to a separator 26 and the separated reaction products are quenched, for example by the introduction through line 40 of water, other vaporisable liquids, or cold catalyst; part of the separated catalyst returns direct to the reactor through line 29, and part is treated with steam in regenerator 38 (where carbonaceous material is removed by the water-gas reaction), and then passes back to the reactor through line 16. Catalyst also passes from the reactor to the regenerator via line 52. By using superheated steam for regeneration, the temperature of the catalyst is raised to 1200-1500 DEG F. in order to supply heat to the butene feed, which is brought to a temperature of 800-1000 DEG F.; the reaction products are quenched to 500-1000 DEG F. Additional heat may be supplied to the regenerator by burning fuel therein. Valves 22, 30 and 35 may be automatically controlled according respectively to the temperature in the reactor or regenerator, the pressure in the reactor, and the level in the separator 25. Suitable catalyst are the oxides of iron, magnesium, and copper, with or without potassium oxide. A potassium compound may be added during regeneration to replace that lost during the process. Specification 557,624, [Group III], is referred to.