Abstract: The isomerization activity of hydroisomerization catalyst is recovered by subjecting the catalyst to a wash using light aromatic solvents at elevated temperature, e.g. toluene at 300.degree. C. This hot aromatic solvent wash may be preceded by a hot hydrogen containing gas strip. Catalyst activity can be maintained by the continuous or periodic addition of light aromatic solvent or light aromatic containing materials to the feeds sent to the isomerization catalyst.
Type:
Grant
Filed:
November 29, 1991
Date of Patent:
May 18, 1993
Assignee:
Exxon Research & Engineering Company
Inventors:
James J. Schorfheide, Biddanda U. Achia
Abstract: The provision and operation of backmix coolers is facilitated by a cooler arrangement that has the backmix portion of the cooler in an inverted position. In this position the heat exchange portion of the cooler is located above the source of hot catalyst. Hot catalyst for heat exchange in the cooler enters and leaves the heat exchange zone from below the location of the heat exchange tubes. The inverted position prevents any collection of debris in the bottom of the cooler, eliminates high velocity impingement of fluidizing medium on the tube, and facilitates the incorporation of the cooler in FCC units by avoiding interference with other equipment.
Abstract: This invention relates to a process for reactivating a dehydrocyclodimerization catalyst. Dehydrocyclodimerization catalysts which contain an aluminum phosphate binder can be deactivated when they are exposed to hydrogen at temperatures above 500.degree. C. The instant process restores substantially all of the catalyst's lost activity. The process involves treating the catalyst with an aqueous solution of a weakly acidic ammonium salt or a dilute acid solution at a temperature of about 50.degree. to about 100.degree. C. for a time of about 1 to about 48 hours. An ammonium nitrate solution is preferred. Next the catalyst is calcined at a temperature of about 500.degree. to about 700.degree. C. for a time of about 1 to about 15 hours to provide a reactivated catalyst. The catalyst can be reactivated several times using this process.
Type:
Grant
Filed:
November 8, 1991
Date of Patent:
May 18, 1993
Assignee:
UOP
Inventors:
Joseph A. Kocal, Christopher D. Gosling, Paul J. Kuchar, Tamotsu Imai
Abstract: An improved apparatus and method for the manufacture of activated carbon wherein a carbonaceous raw material impregnated with a chemical activating agent is treated by controlling the rate of heat transfer to the particles via indirect heating of the activation furnace and simultaneously introducing a flow of independently controlled sweep gas at spaced intervals along the path of travel of the particles through the furnace to more precisely control the activation reaction and the level of densification of the particles during certain stages of treatment. In a more preferred embodiment, the particles are processed in a plurality of treatment stages related to the rate of evolution of water and/or the evolution of water and the chemical activating agent and the rates of heat transfer and the volume flow rate of sweep gas are closely controlled relative to achieving predetermined levels of densification of the particles during each treatment stage and selected levels of activation properties in the end product.
Abstract: Spent hydrotreating catalyst having carbonaceous and metallic deposits and of regular geometric shape after being stripped of process oil is fluidized by flowing air upwardly through the catalyst at a velocity sufficient to expand the bed thereby segregating the catalyst particles into a high activity, upper, less-contaminated fraction and a lower, more-contaminated fraction and recycling the high activity fraction to a hydrotreating process. Optionally, the high activity fraction can be regenerated with carbon burnoff or rejuvenated by acid leaching followed by regeneration with carbon burnoff to further improve catalyst activity.
Type:
Grant
Filed:
October 2, 1991
Date of Patent:
May 11, 1993
Assignee:
Texaco Inc.
Inventors:
David E. Sherwood, Jr., Johnnie R. Hardee, Jr., John A. Lemen
Abstract: A process for the production of an ether-rich additive for gasoline, and more particularly, the production of MTBE, TAME and mixtures thereof from light hydrocarbon streams comprising passing the light hydrocarbon stream, preferably from an FCC feedstock, through a superactivated alumina medium so as to remove nitrogen compounds, mercaptan and water prior to contacting the feedstock with a catalyst under etherification process conditions. The present invention further includes a process for regenerating the spent superactivated alumina mediums used for purifying the feedstock employed in the process for the production of ether-rich additives for gasoline.
Type:
Grant
Filed:
March 6, 1992
Date of Patent:
May 11, 1993
Assignee:
Intevep, S.A.
Inventors:
Marco A. Marquez, Jose C. Gonzalez, Victor J. Degouveia, Francisco Yanez
Abstract: A process for recovering a Group VIII metal from an organic solution is disclosed. The organic solution is contacted with an acidic ion exchange resin that has sulfonic acid active groups. The invention provides an effective and economical way to recover valuable transition metals from dilute organic solutions.
Type:
Grant
Filed:
February 25, 1992
Date of Patent:
May 4, 1993
Assignee:
Arco Chemical Technology, L.P.
Inventors:
Rangasamy Pitchai, Thomas S. Zak, Kurt E. Soring
Abstract: Carbonaceous material is activated to produce a high activity, high density gas-phase activated carbon under conditions which effectively alter the particle pore size distribution to optimize the carbon's mesoporosity. The carbon is particularly suited for application in emission control for vehicles.
Abstract: A reactivated catalyst having optimum activity for hydrocracking and other acid catalyzed chemical conversion processes is prepared by contacting its deactivated counterpart, which contains a crystalline molecular sieve, a Group VIII noble metal hydrogenation component and carbonaceous deposits, with a gas containing molecular oxygen, preferably air, at a temperature between 950.degree. and 1200.degree. F., preferably between about 1050.degree. and 1150.degree. F., for a time sufficient to remove at least a portion of the carbonaceous deposits. When the reactivated catalyst contains a dealuminated Y zeolite that has been ion-exchanged with both noble metal and rare earth metal cations, its activity for hydrocracking in an ammonia-deficient atmosphere can be further increased by a rejuvenation procedure in which the reactivated catalyst is contacted with an aqueous ammonia solution in which an ammonium salt has been dissolved.
Abstract: Lignocellulosic carbonaceous material is activated to produce a high activity, high density gas-phase activated carbon under conditions which effectively alter the particle pore size distribution to optimize the carbon's mesoporosity. Alternative processes are disclosed for producing the carbon, as are its application in emission control for vehicles.
Type:
Grant
Filed:
February 21, 1992
Date of Patent:
April 20, 1993
Assignee:
Westvaco Corporation
Inventors:
Edward D. Tolles, Mitchell S. Dimitri, Charles C. Matthews
Abstract: A process is provided for preparing fibrous or film type activated carbon including the steps of carbonizing a cellulosic material and activating the resulting carbon, each stop occurring at a temperature between 200.degree. C. and 1100.degree. C. in an oxidation-suppressing atmosphere, in which, prior to activation, the cellulosic material or carbon is impregnated with at least one boron-containing compound and at least one phosphorus-containing compound. This impregnation treatment greatly increases the activation rate, so reducing the activation time and therefore energy costs. Higher levels of production of fibrous activated carbons can thus be achieved.
Type:
Grant
Filed:
July 19, 1990
Date of Patent:
April 13, 1993
Inventors:
John M. D. De La Pena, Richard A. Roberts
Abstract: Catalyst supports, catalyst systems, methods for the preparation thereof, and dimerization process therewith are provided catalyst supports are extruded from a thick paste of potassium carbonate and water catalyst systems comprise at least one elemental alkali metal deposited on the catalyst sypport. Optionally, the catalyst system further comprises at least one promoter.
Type:
Grant
Filed:
December 5, 1990
Date of Patent:
April 13, 1993
Assignee:
Phillips Petroleum Company
Inventors:
Paul F. Schubert, Ralph E. Bonnell, Norman L. Freeman, Jr., Denton C. Fentress, Kent E. Mitchell, Richard E. Lowrey, Donald H. Kubicek, Warren M. Ewert
Abstract: The present invention relates to a process for the pretreatment of activated carbon, capable of being employed especially for the purification of concentrated solutions of hydrochloric acid.
Abstract: A process and apparatus for the regeneration of spent FCC catalyst in a single vessel are disclosed. In one embodiment, catalyst is at least partially regenerated in a primary stage comprising a fast or turbulent fluidized bed. The flue gas is discharged up, with some and preferably most of the catalyst discharged laterally, through windows, into a second fluidized bed, preferably disposed as an annulus about the first. In another embodiment a cyclone separator is closely coupled to, but spaced from, the primary regeneration stage, to rapidly separate catalyst from first stage flue gas, and minimize thermal stress.
Abstract: The process is a hydrogen regeneration of spent Group VIII metal modified non-acidic microporous crystalline materials employed as catalysts in dehydrogenation and dehydrocyclization.
Abstract: A relatively simple and more economical method for regenerating activated carbon wherein at least partially spent activated carbon is fed from a portable container directly to a heating zone without the use of liquid to transport the at least partially spent activated carbon to the heating zone. A portable container for use in the activated carbon regeneration method can be used to hold the activated carbon during adsorption processes, during storage of the activated carbon, and during transportation of the activated carbon between an adsorption site and a regeneration site. In the activated carbon regeneration method, the portable container is preferably positioned adjacent a conveyor so that the spent activated carbon can be delivered directly to the conveyor with an auger. The spent activated carbon is then fed directly to the heating zone with the conveyor.
Abstract: A method is disclosed for the preparation of active magnesium hydride-magnesium-hydrogen storage systems, which reversibly absorb hydrogen, with addition of a catalyst for the absorption of hydrogen with the formation of hydride. Magnesium hydride particles.ltoreq.400 .mu.m in diameter are added in an amount of at least 1.2% by weight, based on the magnesium to be hydrogenated, as catalyst during the first hydrogenation to the finely divided magnesium to be hydrogenated. The hydrogenation is carried out at a temperature of .gtoreq.250.degree. C. and a pressure of 0.5 to 5 MPa. The method is carried out with intensive stirring of the material that is being reacted.
Abstract: A process and apparatus for multi-stage fluidized bed regeneration of spent FCC catalyst in a single vessel. At least two isolated relatively dense phase fluidized beds are disposed beneath a common dilute phase region. Spent catalyst discharged into a primary regeneration stage is regenerated to produce flue gas and partially regenerated catalyst, which preferably overflows into the second stage. Flue gas and entrained catalyst from each fluidized bed are processed in two trains of separation means, preferably cyclones. The inlets of each train are disposed above the isolated fluidized beds, and are effectively separated although sharing an open dilute phase region.
Abstract: A reactive membrane for simultaneous removal of heterogeneous and homogeneous impurities such as moisture, oxygen and organic compounds from gases is provided. The membrane comprises a substrate layer having a plurality of pores therein, at least one layer of carbon on the porous substrate layer and coating the pores thereof, and at least one reactive layer of a metal in reduced form capable of reacting with the impurities and chemically bonded to the carbon layer. A method of forming the same is also provided.
Abstract: The present invention is a process for regenerating a sulfur-contaminated, highly selective, large-pore zeolite catalyst. It comprises a multistep process involving exposure of the catalyst to a combination of oxidizing conditions, reducing conditions and treatment with a halogen acid gas. These conditions are effective to agglomerate a Group VIII metal and remove sulfur. Thereafter, the catalyst is oxychlorinated to redisperse the Group VIII metal over the catalyst surface. A carbon removal step is optionally included.
Type:
Grant
Filed:
July 22, 1991
Date of Patent:
May 11, 1993
Assignee:
Chevron Research and Technology Company
Inventors:
Dean A. Van Leirsburg, Donald H. Mohr, Paul W. Tamm, Robert L. Jacobson, Thomas R. Hughes, Charles R. Wilson