Abstract: A mixture comprising non-magnetic solids is separated according to the density difference of its components by contact with a separating medium comprised of a fluidized bed of magnetizable particles which is stabilized by a magnetic means. The separating medium circulates in a closed loop within a contacting vessel or zone such that at least two portions of said separating medium flow in essentially opposite directions transverse to the flow of the fluidizing fluid exiting the medium. This invention is particularly effective for separating mixtures of coal or for separating coal from other solids.
Abstract: A multicomponent feed mixture may be separated into its components continuously by injecting said feed mixture and a carrier fluid into a magnetically stabilized fluidized bed containing adsorbent particles admixed or composited with magnetizable particles. The bed particles continuously move transverse to the flow of the carrier fluid, which serves to fluidize the bed, such that the components of the feed mixture are transported downstream varying distances from the injection point depending upon the adsorption and desorption characteristics of said components. Product streams comprising a portion of the carrier fluid and a portion of the feed mixture containing at least a portion, preferably a major portion, of one of the components can then be recovered from the surface of the bed, the most strongly adsorbed component being transported (and thus recovered) farthest from the injection point.
Abstract: A method of preparing electrically conductive pyrochlore compounds of high surface area and unagglomerated form, having the formulaA.sub.2 [B.sub.2-x A.sub.x ]O.sub.7-yis disclosed wherein A is selected from lead, bismuth and mixtures thereof, B is selected from ruthenium, iridium and mixtures thereof, 0<x.ltoreq.1.0 and 0.ltoreq.y.ltoreq.1. The method involves (1) synthesizing the pyrochlores in an aqueous alkaline reaction medium having a pH of at least about 12.0 and in the presence of an oxygen source (2) displacing the reaction medium with water, (3) atomizing the resultant slurry and (4) freeze drying the resultant product. The pyrochlore compounds thus prepared have a variety of applications including use as oxygen electrodes in electro-chemical devices.
Type:
Grant
Filed:
September 30, 1982
Date of Patent:
April 3, 1984
Assignee:
Exxon Research and Engineering Co.
Inventors:
Harold S. Horowitz, Joseph T. Lewandowski
Abstract: Nonstoichiometric carbon-sulfur compounds have been found to be effective adsorbents for separating organic vapors from a gaseous mixture. Separation of aromatic compounds from gaseous mixtures is particularly effective using such compounds. The spent adsorbent may then be regenerated.
Type:
Grant
Filed:
January 3, 1978
Date of Patent:
September 1, 1981
Assignee:
Exxon Research & Engineering Co.
Inventors:
David W. Savage, Chin H. Chang, John M. Longo
Abstract: A minor portion of the regeneration gas used to regenerate spent fluid catalytic cracking catalyst is employed to combust volatile hydrocarbons in mixture with said spent catalyst prior to said mixture entering the regeneration zone. This serves to reduce and/or minimize transverse oxygen gradients in the dense phase catalyst bed and in the effluent gases therefrom such that excessive or undesirable afterburning in the dilute catalyst phase can be minimized or eliminated.
Abstract: A minor portion of the regeneration gas used to regenerate spent fluid catalytic cracking catalyst is introduced into the regeneration zone in the localized area of the terminus of the spent catalyst line so as to combust the volatile hydrocarbons in mixture with the spent catalyst being transferred from the reaction zone to the regeneration zone. This serves to reduce and/or minimize transverse oxygen gradients in both the dense phase catalyst bed and in the effluent gases therefrom such that excessive or undesirable afterburning in the dilute catalyst phase can be minimized or eliminated.
Abstract: Nonstoichiometric carbon-sulfur compounds have been found to be effective adsorbents for removing a wide variety of organic and/or inorganic materials from liquids, preferably polar liquids. Removal of biorefractory organics, such as aromatics, is particularly effective using such compounds. The spent adsorbent may then be regenerated.
Type:
Grant
Filed:
January 3, 1978
Date of Patent:
May 6, 1980
Assignee:
Exxon Research & Engineering Co.
Inventors:
David W. Savage, Chin H. Chang, John M. Longo
Abstract: Substantial dewatering of a secondary sewage sludge stream is obtained by admixing same with various hydrocarbon oils, the initial sludge/oil weight ratio being maintained in an amount less than 0.6, at shear rates of at least 130 seconds.sup.-1, and allowing the mixture thus formed to settle at temperatures of at least 72.degree. F. Substantially complete disposal of the solids thus removed from the secondary sludge stream can be achieved by subjecting same to evaporation and incineration processes.
Type:
Grant
Filed:
November 19, 1975
Date of Patent:
April 1, 1980
Assignee:
Exxon Research & Engineering Co.
Inventors:
Leonard Berkowitz, Jerome Geyer, Alan Beerbower, William J. Asher
Abstract: A novel composition is formed by suspending a carbonaceous adsorbent in a branched hydrocarbon solvent. In addition, said powdered carbonaceous adsorbent suspended in a hydrocarbon solvent, preferably a branched hydrocarbon solvent, is an effective adsorbent-extractant for removing both soluble and insoluble organic materials from waste water. Use of this suspension as an adsorbent enables the use of a continuous adsorption process having high capacity for removal of contaminants, fast contaminant removal rates and high adsorbent utilization while permitting easy staged contacting. The spent suspension may then be regenerated by vapor stripping or solvent extraction.
Abstract: A minor portion of the regeneration gas used to regenerate spent fluid catalytic cracking catalyst is passed into a distribution means located at the interface between the dense phase catalyst bed and the dilute catalyst phase in the regeneration zone of a fluid catalytic cracking process to combust, at said interface, the carbon monoxide formed in said bed to carbon dioxide. In a preferred embodiment, the level of the dense phase bed can be adjusted to vary the amount of catalyst entrained in the dilute catalyst phase such that the distribution means will be partially submerged. This serves to provide a simple and convenient method to absorb the heat released by the oxidation of carbon monoxide, thereby minimizing or eliminating excessive or undesirable afterburning in the dilute catalyst phase and in equipment downstream thereof.
Abstract: Hydrocarbon conversion catalysts which have become deactivated by the deposition of coke and metal contaminants such as nickel, iron, vanadium, etc., are regenerated under conditions which include temperatures in excess of 1300.degree. F. and the periodic use of an amount of oxygen which is in excess of that required to completely burn the coke to CO.sub.2. In a hydrocarbon conversion process whereby a metal-contaminated heavy feed is contacted at conversion conditions with a cracking catalyst to produce lower boiling hydrocarbon products and a spent catalyst having coke and said metal contaminant deposited thereon and wherein said spent catalyst is reactivated in a regeneration zone at elevated temperatures in the presence of O.sub.2 to produce a regenerated catalyst and a flue gas containing more than 2 vol. % CO, the improvement which comprises periodically increasing the amount of O.sub.2 introduced into said regeneration zone at a temperature in excess of 1300.degree. F. so that the level of O.sub.
Abstract: Sulfur tetrachloride derivatives are prepared by reacting suitable sulfur-containing compounds in hydrogen fluoride with a gas containing molecular chlorine in the presence of one or more acidic halides. Such derivatives can be used to remove water from its solutions in hydrogen fluoride.
Abstract: Silica can be removed effectively from a mixed bed demineralizer containing an anion exchange resin and a cation exchange resin during regeneration by(1) passing from about 30 to about 80 volume % of an anion regenerant solution through only the anion exchange resin,(2) passing the remaining portion of the anion regenerant solution through both the anion exchange resin and the cation exchange resin, and(3) passing a stream of cation regenerant solution through the cation exchange resin.When the anion and cation exchange resins are regenerated according to this procedure, the amount of silica on the resins is reduced such that when silica containing water is passed through the demineralizer during normal operations, the concentration of silica in the treated water as SiO.sub.2 will be less than 0.1, most preferably less than 0.005, milligrams per liter.
Type:
Grant
Filed:
December 15, 1977
Date of Patent:
August 7, 1979
Assignee:
Exxon Research & Engineering Co.
Inventors:
Roger A. Blind, Robert T. Saterbak, Edward I. Wolfe
Abstract: Noble metals on supported zeolite-containing hydrocarbon conversion catalysts, which have been at least partially damaged by thermal and/or hydrothermal stresses resulting in a maldistribution of the supported metal, are redispersed to a highly active, high surface area state by contacting said catalyst with ethylenediaminetetraacetic acid (EDTA), or a salt thereof, to the point of incipient wetness and then removing said acid by heat treatment.
Abstract: H.sub.2 S is removed continuously from H.sub.2 S-rich liquid sulfur by contacting same with an H.sub.2 S-lean carrier gas in more than one discrete contacting stage. Preferably, the liquid sulfur is recirculated in at least one discrete contacting stage to provide better contacting between the sulfur and the carrier gas within said stage.
Type:
Grant
Filed:
June 29, 1977
Date of Patent:
December 26, 1978
Assignee:
Exxon Research & Engineering Co.
Inventors:
Thomas M. Campbell, William H. Ringler, Howard Lerner
Abstract: Anhydrous TaF.sub.5 can be synthesized from a mixture comprising water and fluorotantalic acids by contacting said mixture with a dehydrating agent. Preferably, said mixture is formed by contacting tantalum oxides, tantalum oxide-halides or mixtures thereof with HF. The dehydrating agent should be a compound that contains carbon-chlorine bonds, carbon-bromine bonds or mixtures thereof.
Abstract: Deactivated or partially deactivated hydrocarbon conversion catalysts comprising (a) one or more Lewis acids selected from the group consisting of the fluorides, chlorides and bromides of boron(III), titanium(IV), zirconium(IV), hafnium(IV), phosphorus(V), arsenic(V), tantalum(V), niobium(V) and mixtures thereof and (b) a strong Bronsted acid, may be recovered by contacting said catalysts with hydrogen at elevated temperatures and pressures. The preferred Lewis acid is an acidic halide, preferably tantalum pentafluoride, niobium pentafluoride or mixtures thereof. The preferred Bronsted acid is a hydrogen halide, preferably hydrogen fluoride.
Abstract: A soluble HF/TaF.sub.5 catalyst is prepared in the absence of an organic solvent according to the steps of:(1) contacting tantalum metal with substantially anhydrous liquid HF to form soluble TaF.sub.5, the amount of HF being sufficient to maintain the TaF.sub.5 thus formed as a homogeneous substantially liquid phase catalyst at a temperature ranging from about 0.degree. to 150.degree. C.,(2) contacting the catalyst thus formed with a hydrocarbon feedstock in a hydrocarbon conversion process to form an acid catalyst phase and a hydrocarbon product phase,(3) stripping HF from said catalyst phase with a gas containing molecular hydrogen thereby reducing the mole ratio of HF to TaF.sub.5, and(4) passing the stripped acid catalyst phase from step (3) to the hydrocarbon conversion process, thereby maintaining the mole ratio of HF to TaF.sub.5 within said process at a level between that obtained in step (1) and step (3).
Abstract: An improved method for regenerating a catalytic cracking catalyst which comprises the steps of (1) increasing the temperature of the regeneration zone dense phase catalyst bed to a desired level above that normally employed during the regeneration so as to accelerate the rate of carbon conversion, (2) reducing the coke make in the reaction zone while maintaining the elevated temperature obtained in step (1) so as to increase the oxygen concentration in said regeneration zone so as to establish low levels of carbon monoxide in the flue gas and (3) reducing the temperature of the regeneration zone dense phase catalyst bed below the elevated temperature obtained in steps (1) and (2) while maintaining low levels of carbon monoxide in the flue gas. According to this invention, the flue gas may contain less than 0.05 volume %, preferably less than 0.02 volume %, carbon monoxide and, as such, may be discharged directly to the atmosphere with no discernable effect upon ambient air quality.
Abstract: Hydrocarbon conversion catalysts comprising a metal halide in combination with a Bronsted acid containing fluorine that have become deactivated or partially deactivated by the formation of allyl and alkylaromatic carbonium ion complexes with the acid during contact with a hydrocarbon feedstock may be regenerated by contacting said catalyst, in the presence of molecular hydrogen and under suitable regeneration conditions, with a noble metal hydrogenation component. A preferred catalyst comprises tantalum pentafluoride and hydrogen fluoride. Palladium is the preferred noble metal hydrogenation component.