Abstract: Controlling sulfur oxide emissions from FCC regenerator flue gas by mixing a sulfur sorbent in the circulating inventory and having present in the regeneration zone a chromium/tin sulfur dioxide oxidation promoter.

Abstract: Controlling sulfur oxide emissions from FCC regenerator flue gas by mixing a sulfur sorbent in the circulating inventory and having present in the regeneration zone a chromium/tin sulfur dioxide oxidation promoter.

Abstract: NO.sub.x in flue gas from a regenerator in which an SO.sub.2 oxidation promoter is present is controlled by mixing ammonia with flue gas and passing the mixture through a combustion zone.

Abstract: Sulfur oxides are removed from flue gas in a catalyst regenerator in a fluid catalyst cracking system while liquid-hydrocarbon product yield from the system is maintained at a high level by heating a nonzeolitic, silica-containing catalyst to 800.degree.-1500.degree. F.; impregnating 0.1 to 25 weight percent aluminum onto the catalyst particles; and cycling the resulting particles through the cracking reactor and catalyst regenerator in the cracking system, the impregnated catalyst being particularly adaptable for cracking heavy, metals-containing feeds such as residua.

Abstract: A waste gas containing sulfur dioxide is desulfurized by contacting the gas with phosphorus-promoted sodium vanadate disposed upon porous alumina having a phosphorus-to-vanadium atomic ratio in the range 0.2-1.8 to 1.

Abstract: A process for removing coke from particulate catalyst is disclosed, in which nitrogen oxides are formed during combustion of nitrogen-containing coke in an oxidizing atmosphere in the presence of a carbon monoxide combustion promoter in a lower portion of a fluidized bed, and the nitrogen oxides are reacted to form free nitrogen by introducing a vaporizable fuel into an upper part of the fluidized bed.

Abstract: In regeneration of a cracking catalyst using platinum to catalyze combustion of CO, the amount of nitrogen oxides formed is decreased by empolying a combustion promoter containing, for each part of platinum, from 0.01 to 1 part of iridium or rhodium.

Abstract: In removing sulfur oxides from flue gas in a cracking catalyst regenerator in the presence of a silica-containing particulate catalyst by reacting the sulfur oxides with alumina in a particulate solid other than the catalyst, activity loss in the alumina as a result of migration of silica from the catalyst particles to the alumina-containing particles is decreased by using alumina-containing particles which contain sodium, manganese or phosphorus.

Abstract: In removing sulfur oxides from flue gas in a cracking catalyst regenerator in the presence of a silica-containing particulate catalyst by reacting the sulfur oxides with alumina in a particulate solid other than the catalyst, activity loss in the alumina as a result of migration of silica from the catalyst particles to the alumina-containing particles is lessened by using alumina-containing particles which contain sodium, manganese or phosphorus.

Abstract: A process is provided for adsorbing sulfur dioxide impurity from an impure gas and producing a hydrogen sulfide-rich gas. In the process, a first adsorbate containing oxidized sulfur is produced by contacting the impure gas with an adsorbent comprising a composite of an alumina support and sodium and vanadium oxides. A second adsorbate containing reduced sulfur is produced by contacting said first adsorbate with carbon monoxide. A gas rich in hydrogen sulfide is then produced by contacting said second adsorbate with water vapor at a temperature in the range 120.degree. C. to 815.degree. C.

Abstract: Carbon monoxide and sulfur oxides are removed from flue gas produced in a catalyst regenerator in an FCC system and sulfur from the flue gas is shifted to form hydrogen sulfide, which is recovered in the gases removed from the cracking reactor in the system by introducing sufficient molecular oxygen into the catalyst regenerator to provide an atmosphere therein having a molecular oxygen concentration of at least 0.1 volume percent, reacting carbon monoxide in the regenerator flue gas with oxygen in contact with a particulate carbon monoxide combustion promoter physically admixed with the cracking catalyst, reacting sulfur oxides in the regenerator flue gas with silica-free alumina included as a discrete phase in the FCC catalyst to form a sulfur-containing solid in the catalyst, and forming hydrogen sulfide in the cracking reactor by contacting the sulfur-containing solid with the hydrocarbon feed.

Abstract: Carbon monoxide and sulfur oxides are removed from catalyst regenerator flue gas in an FCC system using a nonzeolitic cracking catalyst and sulfur from the flue gas is shifted to form hydrogen sulfide, which is recovered in the gases removed from the cracking reactor in the system by reacting carbon monoxide in the regenerator flue gas with oxygen in contact with a particulate carbon monoxide combustion promoter, reacting sulfur oxides in the regenerator flue gas with particulate alumina physically mixed with the nonzeolitic catalyst to form a sulfur-containing solid, and forming hydrogen sulfide in the cracking reactor by contacting the sulfur-containing solid with the hydrocarbon feed.

Abstract: The amount of sulfur oxides in flue gas evolved in a catalyst regenerator in a catalytic cracking system is lowered by incorporating into the cracking catalyst, before using the catalyst in the cracking system, finely divided, high surface area alumina which has been calcined at 700.degree.-1600.degree.0 F. before incorporation into the catalyst. Sulfur oxides react with the calcined alumina in the regenerator to form a sulfur-containing solid. The sulfur-containing solid reacts with hydrocarbon to form fluid sulfur compounds in the FCC reactor, and the sulfur compounds exit the reactor mixed with the cracked hydrocarbons.

Abstract: Sulfur oxides in flue gas formed during cracking catalyst regeneration are reacted with a zeolitic crystalline aluminosilicate containing sodium cations in the catalyst regenerator to form a sulfur-containing solid, and the sulfur component is removed from the crystalline aluminosilicate in the cracking reactor by contacting the sulfur-containing solid with the hydrocarbon feed.

Abstract: Sulfur oxides are removed from a gas and the sulfur is converted to hydrogen sulfide by the steps of: (1) reacting sulfur oxides in the gas with alumina to form a solid sulfur-containing compound and remove sulfur oxides from the gas; and (2) contacting the solid compound resulting from step (1) with a hydrocarbon at a temperature of about 800.degree.-1300.degree. F. and reacting the solid sulfur-containing compound with components of the hydrocarbon to form hydrogen sulfide.

Abstract: Carbon monoxide and sulfur oxides are removed from flue gas produced in a catalyst regenerator in an FCC system and sulfur from the flue gas is shifted to form hydrogen sulfide, which is recovered in the gases removed from the cracking reactor in the system by introducing sufficient molecular oxygen into the catalyst regenerator to provide an atmosphere therein having a molecular oxygen concentration of at least 0.1 volume percent, reacting carbon monoxide in the regenerator flue gas with oxygen in contact with a particulate carbon monoxide combustion promoter physically admixed with the cracking catalyst, reacting sulfur oxides in the regenerator flue gas with silica-free alumina included as a discrete phase in the FCC catalyst to form a sulfur-containing solid in the catalyst, and forming hydrogen sulfide in the cracking reactor by contacting the sulfur-containing solid with the hydrocarbon feed.

Abstract: Carbon monoxide and sulfur oxides are removed from flue gas produced in a catalyst regenerator in an FCC system and sulfur from the flue gas is shifted to form hydrogen sulfide, which is recovered in the gases removed from the cracking reactor in the system by reacting carbon monoxide in the regenerator flue gas with oxygen in contact with a particulate carbon monoxide combustion promoter, reacting sulfur oxides in the regenerator flue gas with particulate alumina physically mixed with the FCC catalyst to form a sulfur-containing solid, and forming hydrogen sulfide in the cracking reactor by contacting the sulfur-containing solid with the hydrocarbon feed.

Abstract: Sulfur oxides are removed from flue gas in a catalyst regenerator in a fluid catalyst cracking system while liquid-hydrocarbon product yield from the system is maintained at a high level by heating a particulate silica-containing cracking catalyst to 800-1500.degree. F; impregnating 0.1 to 25 weight percent aluminum onto the catalyst particles; and cycling the resulting particles through the cracking reactor and catalyst regenerator in the cracking system.

Abstract: Sulfur oxides are removed from a gas and the sulfur is converted to hydrogen sulfide by the steps of: (1) reacting sulfur oxides in the gas with alumina to form a solid sulfur-containing compound and remove sulfur oxides from the gas; and (2) contacting the solid compound resulting from step (1) with a hydrocarbon at a temperature of about 800.degree.-1300.degree. F and reacting the solid sulfur-containing compound with components of the hydrocarbon to form hydrogen sulfide.

Abstract: A process is provided for preparing catalytically active emerald green colored alumina by contacting colorless alumina with carbonyl sulfide. This material catalyzes the reduction of sulfur dioxide by carbon monoxide.