Abstract: The present invention discloses aqueous methods for enhancing the acid sites of fluid catalytic cracking (FCC) catalysts. The methods comprise the steps of contacting an FCC catalyst, either spent or fresh, with an aqueous solution comprising water, an inorganic acid substantially free of chloride and aluminum. The acid is preferably sulfurous or sulfuric acid. The aluminum is provided by an aluminum source selected from the group consisting of the alumina trihydrates and aluminum oxide. Chloride contamination of the aluminum source should be minimal, preferably less than about 1000 ppm chloride, more preferably less than about 200 ppm chloride. The pH of the aqueous solution is adjusted to about 3-12 by the addition of a sufficient quantity of ammonium hydroxide. The FCC catalyst is added to this solution, preferably with stirring, in a weight ratio of about 1 part catalyst to about 1-10 parts water to prepare an aqueous slurry.

Abstract: The present invention discloses aqueous methods for enhancing the acid sites of fluid catalytic cracking (FCC) catalysts. The methods comprise the steps of contacting an FCC catalyst, either spent or fresh, with an aqueous solution comprising water, and a source of both phosphorus and aluminum. Optionally the solution includes sulfurous or sulfuric acid. The phosphorus is provided by phosphoric acid, phosphorous acid or ammonium dihydrogen phosphate. The aluminum is provided by an aluminum source selected from the group consisting of the alumina trihydrates and aluminum oxide. Chloride contamination of the aluminum source should be minimal, preferably less than about 1000 ppm chloride, more preferably less than about 200 ppm chloride. The pH of the aqueous solution is adjusted to about 3-12 by the addition of a sufficient quantity of an aqueous ammonium solution.

Abstract: An improved sulfider is provided for receiving high temperature catalysts from the hydrocarbon cracking operation and subjecting the catalyst to a sulfur-containing gas. The sulfider unit includes a plurality of gas injector tubes each individually removable from the sulfider while gas is continually injected into the sulfider treatment chamber through other of the injection tubes. Each injector tube may extend through a lowermost end of the sulfider, and has a central tube axis arranged substantially vertically when the tube is mounted to the sulfider housing. Fluid output ports are provided in sidewalls of an upper portion of the tube, and the tubes may be continually operated for extended periods of time without significant plugging problems. A service valve and packing unit associated with each injector tube enable partial removal of the tube from the treatment chamber without leakage of hydrogen sulfide gas, followed by closing of the valve and complete removal of the tube and packing unit.

Abstract: An improved sulfider is provided for receiving high temperature catalysts from a hydrocarbon cracking operation and subjecting the catalyst to a sulfur-containing gas. The treating unit includes an outer metal housing and first refractory layer within the metal housing for minimizing heat loss from the treatment unit. A second refractory layer is provided within the first refractory layer and defines an interior chamber within the treatment unit, and a plurality of heating units are spaced circumferentially along the interface of the first and second refractory layers. The heating units substantially minimize the temperature differential across the second refractory layer and thereby minimize the heat loss from the high temperature catalyst within the chamber. The catalyst is continually passed into and out from the chamber, and the sulfur-containing gas is injected into a lower portion of the chamber to pass through the high temperature bed formed by the catalyst.

Abstract: A demetallization process for catalysts used for chemical conversion of hydrocarbons, the catalysts containing at least vanadium as a metal poison, wherein the poisoned catalyst is contacted in a sulfiding zone with a sulfiding agent and a hydrocarbon having a minimum boiling point of about 300.degree. F., the hydrocarbon being at least partially vaporizable at the temperature in the sulfiding zone.