Catalyst regeneration process

Claim 2

In a process for reactivating catalysts which have become inactive due to deposition of from about 3 to 20% of carbonaceous deposits on their surfaces by contacting the catalyst with a free oxygen-containing gas at elevated temperature to burn off the carbonaceous deposits, the improvement which comprises: (a) covering the catalyst with liquid water and maintaining the liquid water in contact with the catalyst for a least one hour, then (b) contacting the catalyst with a free oxygen-containing gas at a temperature in the range about 300°-600° F. for a time sufficient to evaporate substantially all of the water from the catalyst and concurrently remove a portion of the carbonaceous deposits, and (c) thereafter contacting the dried catalyst with a free oxygen-containing gas at a temperature in the range about 600°-900° F. to burn the remaining carbonaceous deposits.

Claim 3

A process for regenerating hydrotreating catalysts comprised of Group VIb, VIIb or VIII metals or mixtures of these metals disposed on a rugged porous support which have become deactivated during use by accumulation of from about 3 to 20% of carbonaceous materials and of sulfur materials on their surfaces which comprises: (a) wetting the catalyst with liquid water and maintaining the catalyst in contact with the liquid water for at least one hour, then (b) contacting the catalyst with a regenerating gas having free oxygen content in the range 14 to 21% by volume at a temperature in the range 300°-600° F. for a time sufficient to evaporate substantially all of the water from the catalyst and concurrently remove a portion of the carbonaceous materials from the catalyst, (c) then contacting the catalyst with a free oxygen-containing gas in a regeneration zone, said gas being introduced at a temperature such that the temperature of the gas effluent from the regeneration zone is at a temperature in the range about 400°-650° F. for a time sufficient to burn substantially all of the sulfur from the catalyst, and then (d) contacting the catalyst with a free oxygen-containing gas in a regeneration zone, said gas being introduced at a temperature such that the gas effluent from the regeneration zone is at a temperature in the range about 650°-900° F. for a time sufficient to burn substantially all of the remaining carbonaceous material from the catalyst.

Claim 4

A process for regenerating hydrotreating catalysts comprised of Group VIb, VIIb or VIII metals or mixtures of these metals disposed on a rugged porous support which have become deactivated during use by accumulation of from about 3 to 20% of carbonaceous materials and of sulfur materials on their surfaces which comprises: (a) wetting the catalyst with liquid water and maintaining the catalyst in contact with the liquid water for at least one hour, then (b) contacting the catalyst with a regenerating gas having free oxygen content in the range 14 to 21% by volume at a temperature in the range 300°-600° F. for a time sufficient to evaporate substantially all of the water from the catalyst and concurrently remove a portion of the carbonaceous materials from the catalyst, (c) then contacting the catalyst with a free oxygen-containing gas in a regeneration zone, said gas being introduced at a temperature such that the temperature of the gas effluent from the regeneration zone is at a temperature in the range about 400°-650° F. for a time sufficient to burn substantially all of the sulfur from the catalyst, and then (d) contacting the catalyst with a free oxygen-containing gas in a regeneration zone, said gas being introduced at a temperature such that the gas effluent from the regeneration zone is at a temperature in the range about 650°-900° F. for a time sufficient to burn substantially all of the remaining carbonaceous material from the catalyst.

Claim 5

The process defined in claim 2 wherein the regeneration zone is of the rotary kiln type and the oxygen content of the free oxygen-containing gas employed in each of steps (b), (c) and (d) is in the range about 14 to 21% by volume.

Claim 6

In a process for regenerating hydrotreating catalysts, comprises of Group VIb, VIIb or VIII metals or mixtures of metals disposed on a rugged support, which have become deactivated during the course of use by accumulation of from about 3 to 20% carbonaceous materials on their surfaces by contacting the deactivated catalysts with a free oxygen-containing gas at elevated temperature to burn off the carbonaceous materials, the improvement which comprises: (a) wetting the catalyst with liquid water, (b) contacting the catalyst with a gas having a free oxygen content in the range 14 to 21% by volume at a temperature in the range 300°-600° F. for a time sufficient to evaporate substantially all of the water from the catalyst and concurrently remove a portion of the carbonaceous materials from the catalyst, and (c) thereafter contacting the dried catalyst with a free oxygen-containing gas at a temperature above that employed in step (b) to burn the remaining carbonaceous materials from the catalyst.

Claim 7

In a process for regenerating hydrotreating catalysts, comprises of Group VIb, VIIb or VIII metals or mixtures of metals disposed on a rugged support, which have become deactivated during the course of use by accumulation of from about 3 to 20% carbonaceous materials on their surfaces by contacting the deactivated catalysts with a free oxygen-containing gas at elevated temperature to burn off the carbonaceous materials, the improvement which comprises: (a) wetting the catalyst with liquid water, (b) contacting the catalyst with a gas having a free oxygen content in the range 14 to 21% by volume at a temperature in the range 300°-600° F. for a time sufficient to evaporate substantially all of the water from the catalyst and concurrently remove a portion of the carbonaceous materials from the catalyst, and (c) thereafter contacting the dried catalyst with a free oxygen-containing gas at a temperature above that employed in step (b) to burn the remaining carbonaceous materials from the catalyst.

Claim 8

In a process for regenerating hydrotreating catalysts, comprises of Group VIb, VIIb or VIII metals or mixtures of metals disposed on a rugged support, which have become deactivated during the course of use by accumulation of from about 3 to 20% of carbonaceous materials and of sulfur materials on their surfaces by contacting the deactivated catalysts with a free oxygen-containing gas at elevated temperature to burn off the carbonaceous and sulfur materials, the improvement which comprises: (a) wetting the catalyst with liquid water and maintaining the liquid water in contact with the catalyst for a period in excess of one hour, then (b) contacting the catalyst with free oxygen-containing gas at a temperature in the range 300°-600° F. for a time sufficient to evaporate substantially all of the water from the catalyst and concurrently remove a porton of the carbonaceous materials from the catalyst, and (c) thereafter contacting the dried catalyst with a free oxygen-containg gas at a temperature above that employed in step (b) to burn the remaining carbonaceous and sulfur materials from the catalyst.

Claim 9

In a process for regenerating hydrotreating catalysts, comprises of Group VIb, VIIb or VIII metals or mixtures of metals disposed on a rugged support, which have become deactivated during the course of use by accumulation of from about 3 to 20% of carbonaceous materials and of sulfur materials on their surfaces by contacting the deactivated catalysts with a free oxygen-containing gas at elevated temperature to burn off the carbonaceous and sulfur materials, the improvement which comprises: (a) wetting the catalyst with liquid water and maintaining the liquid water in contact with the catalyst for a period in excess of one hour, then (b) contacting the catalyst with free oxygen-containing gas at a temperature in the range 300°-600° F. for a time sufficient to evaporate substantially all of the water from the catalyst and concurrently remove a porton of the carbonaceous materials from the catalyst, and (c) thereafter contacting the dried catalyst with a free oxygen-containg gas at a temperature above that employed in step (b) to burn the remaining carbonaceous and sulfur materials from the catalyst.