Abstract: A purifying catalyst for the exhaust gas from the internal combustion engine of an automobile, for example, is disclosed which excels in the purifying ability in quick response to the atmosphere of the exhaust gas largely varying with changes in the operating condition of the engine involving such phases as idling, acceleration, constant-speed drive, and deceleration. The purifying catalyst contains rhodium, palladium, a cerium compound, and a refractory inorganic oxide as catalytic components carried on a refractory carrier and comprises at least two catalyst layers, namely a catalyst layer containing the cerium compound and a catalyst layer containing palladium.

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 air lance comprises a plastic tube supplied with air at high pressure and having an air outlet. The lance is inserted into catalyst tubes and supplies air for breaking up the catalyst for removal by vacuum means. An air-powered reel is used to dispense and retrieve the plastic lance when emptying the catalyst tubes.

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.

Abstract: A catalyst trough containing multiple guide tubes in registry with the tubes of a multi-tube catalytic reactor is utilized to unload catalysts therefrom with maximum dust containment and maximum catalyst recovery. The catalyst recovery trough contains an outlet collar connected to an outlet line and a positive fastening system whereby the trough is fixedly but detachably connected to the tube sheet of the reactor. The guide tubes extend vertically upwardly from the bottom of the trough and are open in the bottom so as to allow the provision of flexible steel rods or "fish tapes", which may or may not be equipped with high-fluid pressure tubes as air-lances for feeding into the tubes of the reactor, which are on center with the guide tubes of the trough. In this manner any catalytic material which is stuck or bridged across the catalytic tubes may be dislodged so as to fall by gravity into the recovery trough and into an outlet line for recovery.

Abstract: A catalyst trough containing multiple guide tubes in registry with the tubes of a multi-tube catalytic reactor is utilized to unload catalysts therefrom with maximum dust containment and maximum catalyst recovery. The catalyst recovery trough contains an outlet collar connected to an outlet line and a positive fastener whereby the trough is fixedly but detachably connected to the tube sheet of the reactor. The guide tubes extend vertically upwardly from the bottom of the trough and are open in the bottom so as to allow the provision of flexible steel rods or "fish tapes", which may or may not be equipped with high-fluid pressure tubes as air-lances for feeding into the tubes of the reactor, which are on center with the guide tubes of the trough. In this manner any catalytic material which is stuck or bridged across the catalytic tubes may be dislodged so as to fall by gravity into the recovery trough and into an outlet line for recovery.

Abstract: A catalyst trough containing multiple guide tubes in registry with the tubes of a multi-tube catalytic reactor is utilized to unload catalysts therefrom with maximum dust containment and maximum catalyst recovery. The catalyst recovery trough contains an outlet collar connected to an outlet line and a positive fastening means whereby the trough is fixedly but detachably connected to the tube sheet of the reactor. The guide tubes extend vertically upwardly from the bottom of the trough and are open in the bottom so as to allow the provision of flexible steel rods or "fish tapes", which may or may not be equipped with high-fluid pressure tubes as air-lances for feeding into the tubes of the reactor, which are on center with the guide tubes of the trough. In this manmner any catalytic material which is stuck or bridged across the catalytic tubes may be dislodged so as to fall by gravity into the recovery trough and into an outlet line for recovery.

Abstract: A catalyst loading hopper suitable for positioning in vertical position above a reactor vessel, having an inlet at its upper end, a catalyst outlet at its lower end and a diagonally-disposed baffle extending downwardly across the hopper but terminating short of one of the walls of the hopper and a weir adjustably arranged so as to control the flow of catalysts through the hopper. There is a dust outlet at the top of the hopper, which may be connected to a conduit so as to draw dust away from the upper end of the hopper and a screen at the bottom of the hopper to separate the catalyst from any fines or undersized catalyst particles. The screen feeds into a catalyst outlet which, in turn, feeds into a conduit, which extends into the reactor vessel so as to allow arrangement of the cleaned catalyst pellets in layers in the vessel. A gas nozzle opens in the wall of the hopper and allows dust to be blown from the catalyst pellets and through the dust outlet to be collected in a suitable filter.

Abstract: A modular multi-tube catalyst loading funnel comprises a series of funnel modules, each equipped with a rotatable stirring rod, an opening at the bottom, and a variable-speed drive. With the apparatus, it is possible to control the drop rate of catalyst pellets in each of the funnels, by adjusting the speed of rotation of the metering rods. If more control is required, the metering rods may be raised or lowered in each funnel module to increase or decrease the speed of catalyst drop. Additionally, it is possible to utilize metering rods with various end configurations to alter the speed of the catalyst drop in the multitube catalytic reactors.