Process for the reactivation of nickel-alumina catalysts
First Claim
1. In a process for the production of hydrogen and carbon monoxide from a low molecular weight hydrocarbon by contact with a fluidized bed of nickel-on-alumina catalyst at elevated temperature in the presence of steam and oxygen, in a reaction zone operated in a net reducing atmosphere, the steps comprisingwithdrawing a portion of said catalyst and contacting said catalyst with an oxygen-containing gas at a temperature elevated sufficiently to convert the nickel component of said catalyst to nickel aluminate, and disperse said nickel aluminate within the alumina support, without sintering said alumina support, andrecycling said catalyst after contact with the oxygen-containing gas to the reaction zone to reduce the nickel aluminate component of the catalyst, and increase the activity of the catalyst vis-a-vis that of the catalyst initially withdrawn from the reaction zone.
1 Assignment
0 Petitions
Accused Products
Abstract
A process for the reactivation, or rejuvenation of a nickel-alumina catalyst employed in the production of a gas comprised of an admixture of hydrogen and carbon monoxide, or synthesis gas, by the conversion, in a reactor, or reaction zone, of light hydrocarbons in a fluidized bed of the catalyst at elevated temperature, in the presence of steam and oxygen. Catalyst reactivation is accomplished by withdrawing a portion of the catalyst from the fluidized bed of the reactor and treating the catalyst in an oxidation zone at temperature sufficient to oxidize and convert the nickel component of the catalyst to nickel aluminate and disperse said nickel aluminate within the alumina support, and then recycling the treated catalyst to the reactor, or reaction zone, to reactivate and increase the activity of the catalyst. The catalyst, on reduction in the reactor, or reaction zone, is provided an additional boost in activity by washing, treating or contacting the catalyst from the elevated temperature oxidation zone with an acid sufficient to remove trace impurities without removing any substantial amount of the nickel aluminate, and without forming a residue on the catalyst surface. The normal tendency of the catalyst to agglomerate at reaction conditions is also reduced by the acid treatment.
26 Citations
22 Claims
-
1. In a process for the production of hydrogen and carbon monoxide from a low molecular weight hydrocarbon by contact with a fluidized bed of nickel-on-alumina catalyst at elevated temperature in the presence of steam and oxygen, in a reaction zone operated in a net reducing atmosphere, the steps comprising
withdrawing a portion of said catalyst and contacting said catalyst with an oxygen-containing gas at a temperature elevated sufficiently to convert the nickel component of said catalyst to nickel aluminate, and disperse said nickel aluminate within the alumina support, without sintering said alumina support, and recycling said catalyst after contact with the oxygen-containing gas to the reaction zone to reduce the nickel aluminate component of the catalyst, and increase the activity of the catalyst vis-a-vis that of the catalyst initially withdrawn from the reaction zone.
-
11. In a process for the production of hydrogen and carbon monoxide from a low molecular weight hydrocarbon by contact with a fluidized bed of contaminated nickel-on-alumina catalyst at elevated temperature in the presence of steam and oxygen, in a reaction zone operated in a net reducing atmosphere, the steps comprising
withdrawing a portion of said catalyst and contacting said catalyst with an oxygen-containing gas at temperature elevated sufficiently to convert the nickel component of said catalyst to nickel aluminate, and disperse said nickel aluminate within the alumina support, without sintering said alumina support, contacting said catalyst, after contact with said oxygen-containing gas, with an acid solution sufficient to dissolve and remove contaminants from the surface of the catalyst without dissolving the nickel aluminate, and recycling said catalyst to the reaction zone to reduce the nickel aluminate component of the catalyst, increase the activity of the catalyst, and lessen the tendency of the catalyst to agglomerate on recycle to the reaction zone.
-
18. In a process for the production of hydrogen and carbon monoxide from a low molecular weight hydrocarbon by contact with a fluidized bed of nickel-on-alumina catalyst at elevated temperature in the presence of steam and oxygen, in a reaction zone operated in a net reducing atmosphere, the steps comprising
withdrawing a portion of said nickel-on-alumina catalyst from the reaction zone and classifying the catalyst in fractions according to size, including a coarse fraction wherein the average particle size diameters are greater than about 90 microns, contacting said coarse fraction of catalyst with an oxygen-containing gas at a temperature elevated sufficiently to convert the nickel component of said catalyst to nickel aluminate, and disperse said nickel aluminate within the alumina support, without sintering said alumina support, and recycling said catalyst after contact with the oxygen-containing gas to the reaction zone to reduce the nickel aluminate component of the catalyst, and increase the activity of the catalyst vis-a-vis that of the catalyst initially withdrawn from the reaction zone.
Specification