Abstract: Catalyst in a slurry phase reactor is rejuvenated and uniformly distributed in said reactor using a substantially vertical draft tube fully immersed in the slurry which utilizes a rejuvenating gas injected substantially near the bottom of the substantially vertical draft tube whereby catalyst near the bottom of the slurry phase reactor is drawn up the draft tube and discharged from the top of the draft tube near the top of the slurry phase in said reactor.
Type:
Grant
Filed:
December 18, 1992
Date of Patent:
December 7, 1993
Assignee:
Exxon Research & Engineering Company
Inventors:
Larry E. Pedrick, Charles H. Mauldin, William C. Behrmann
Abstract: A mixture of methane, water and carbon dioxide can be effectively converted to carbon monoxide and hydrogen by subjecting the mixture to microwave radiation in the presence of at least one plasma initiator that is capable of initiating an electric discharge in an electromagnetic field.
Abstract: A method for joining bimetallic tubulars and a bimetallic tubular weld configuration which ensures both a continuous corrosion resistant inner lining across the joint as well as the required mechanical strength.
Abstract: A composition of matter having utility in lubricant formulation, said composition being the reaction product of adenine, alkoxylated amine and hydrocarbyldithiobenzoic acid and having the formula (I): ##STR1## where R is hydrogen or a hydrocarbyl group of 1 to 20 carbon atoms, R.sup.1 is a hydrocarbyl group of 2 to 22 carbon atoms, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 are each independently hydrogen, a hydrocarbyl group containing from 1 to 24 carbon atoms or a hydroxy group with the proviso that at least one of R.sup.2 to R.sup.5 is a hydrocarbyl group, x and y are each independently integers of from 1 to 15 with the proviso that the sum of x+y is from 2 to 20, and a, b and c are independent numbers from 1.0 to 3.0 wherein the ratios between a:b, a:c and b:c range from 1.0:3.0 to 3.0:1.0.
Abstract: Catalyst which has become deactivated during a hydrocarbon synthesis (HCS) process is reactivated - rejuvenated using an external reactivation - rejuvenation vessel resulting in a multiple HCS reaction - catalyst rejuvenation reactor vessel design. Flow of the catalyst is synthesis product slurry from the reactor vessel to the rejuvenation vessel and the flow of rejuvenated catalyst back to the reactor vessel are driven by gravity only.
Abstract: By this invention there is provided a catalyst composition comprising a Group IVB oxide, an amorphous silica-alumina support having dispersed thereon a rare earth oxide, which as herein used also includes yttrium oxide, and a metal(s) selected from the group consisting of Group VIII noble metal(s), mixtures of Group VIII noble metal(s) and tin, mixtures of Group VIII noble metal(s) and rhenium, and mixtures of Group VIII noble metal(s), tin and rhenium. The amorphous silica-alumina support contains at least about 50% silica by weight. The catalyst can function as a hydrocarbon conversion catalyst in reactions where platinum on halided (Cl,F)-alumina is typically used.
Type:
Grant
Filed:
July 22, 1992
Date of Patent:
October 19, 1993
Assignee:
Exxon Research & Engineering Company
Inventors:
Stuart L. Soled, Gary B. McVicker, William E. Gates, Sabato Miseo
Abstract: The present invention relates to a process for removing hetero-atoms from a hydrocarbonaceous feedstock using novel catalysts comprised of highly dispersed molybdenum sulfide promoted with a noble metal such that the noble metal is in an oxidation state greater than 0 and coordinated to S. The noble metal is selected from Pt, Pd, Rh, and Ir. It is preferred that the catalysts of be prepared from a precursor composition selected from platinum ethoxyethyl xanthate or platinum dithiocarbamate. Additionally, the catalyst may include a promotor sulfide such as nickel sulfide, cobalt sulfide or iron sulfide, etc. or mixtures thereof.
Type:
Grant
Filed:
October 1, 1990
Date of Patent:
October 12, 1993
Assignee:
Exxon Research & Engineering Company
Inventors:
Gophal H. Singhal, Leo D. Brown, X. B. Cox, III, Thomas R. Halbert
Abstract: Catalyst particle distribution and mixing in slurry part of bubble columns is improved by introducing a secondary suspending fluid into the columns at locations within the lower 20% of the vertical height of the column but above the gas distributor normally located at or near the bottom of the columns.
Abstract: A process for reducing smoke emitted from a two-cycle internal combustion engine wherein the engine is operated with a lubricant oil-fuel mixture containing certain quaternary ammonium hydroxides. A preferred quaternary ammonium hydroxide is tricapryl methyl quaternary ammonium hydroxide.
Abstract: Rare earth oxides, such as Nd.sub.2 O.sub.3 disperse onto the surface of SiO.sub.2 /Al.sub.2 O.sub.3 and act as weakly basic titrants. This lowers the acidity of SiO.sub.2 /Al.sub.2 O.sub.3 to close to that of chlorided alumina, as shown by model compound reaction tests. This support also disperses a noble metal such as Pt much better than undoped SiO.sub.2 /Al.sub.2 O.sub.3 and similar to chlorided alumina. Platinum on the rare earth modified silica alumina can function as a hydrocarbon conversion catalyst in reactions where Pt/chlorided Al.sub.2 O.sub.3 is used, such as in reforming, and isomerization, especially wax isomerization.
Type:
Grant
Filed:
August 20, 1992
Date of Patent:
September 28, 1993
Assignee:
Exxon Research & Engineering Company
Inventors:
Stuart L. Soled, Gary B. McVicker, William E. Gates
Abstract: Zeolite L with flat basal planes, and reduced crystallite size is prepared in a synthesis modified by the addition of small amounts of additional metal such as magnesium, calcium, barium, cobalt, zinc, chromium, manganese or nickel. The addition of these metals also suppresses unwanted zeolite W formation even when the synthesis would otherwise form this zeolite.
Abstract: The present invention includes new polyimide/polyester copolymers without pendent carboxyl groups, a method for their synthesis, and their use as membranes for aromatics/saturates separation.
Type:
Grant
Filed:
August 14, 1992
Date of Patent:
August 31, 1993
Assignee:
Exxon Research & Engineering Company
Inventors:
W. S. Winston Ho, Guido Sartori, Suh J. Han
Abstract: A multi-element housing is disclosed for the containment of multiple membrane separation elements in parallel. The multi-element housing is characterized in that the elements are grouped in parallel with a feed/retentate zone, defined by a space enclosed by two tube sheets arranged at the same end of the elements. The central mandrels of the elements pass through the feed/retentate zone space defined by the two tube sheets and empty permeate outside the defined space into a permeate collection zone from which it is removed, while the tube sheet directly attached to the element is in open relationship to the interior of the membrane element and retentate accumulates in the space between the top tube sheet and the bottom tube sheet from which it is removed.
Type:
Grant
Filed:
July 29, 1992
Date of Patent:
August 24, 1993
Assignee:
Exxon Research & Engineering Company
Inventors:
Dean L. Smith, Jr., Charles P. Darnell, Tan-Jen Chen, Richard J. Basile, Burghard H. Ruterbories, David H. Hopkins
Abstract: A hollow fiber permeator is described which permits counter-current flow in the passage of feed/retentate and permeate-sweep streams. The permeator comprises a bundle of hollow fibers compartmentalized using a series of concentric shells or a spiral wrap extending the entire length of the hollow fibers. The rings or spiral wrap are perforated along the top and bottom to permit even flow distribution through each of the compartments defined by the concentric rings or spiral wrap so that the linear flow rate down the length of the permeator is similar for each compartment.
Abstract: The solvent extraction of aromatics containing oil using a selective aromatics extraction solvent to produce an aromatics rich extract phase and an oil rich/aromatics lean raffinate is improved by the steps of subjecting the extract phase to a membrane separation step to produce a permeate phase and a retentate phase passing the retentate phase to a settling zone wherein the retentate phase spontaneously separates into two liquid phases, and recycling the upper phase to the extraction zone, either to the feed inlet or to the bottom of the extract reflux zone to thereby increase the raffinate oil recovered from the extraction tower. Alternatively or in addition to the above, a side stream can be taken from an intermediate zone of the extraction zone (e.g. extraction tower) and fed to a membrane separation to produce a solvent rich permeate and an oil rich retentate.
Abstract: A coking process wherein a heavy hydrocarbonaceous chargestock is mixed with a minor amount of coal and preheated to a temperature from about 500.degree. F. up to, but not including, coking temperatures. The pretreated mixture is then reacted in a coking zone at coking conditions.
Abstract: This invention relates to a method for producing asphalt that has improved low temperature properties. More specifically, the penetration and Penetration Index of an asphalt can be increased if the asphalt is heat soaked in the presence of a dehydrogenation agent at a temperature above the temperature at which oxidation of the asphalt occurs and below the temperature at which coking is initiated. Polyvinyl chloride and a chlorinated wax are preferred dehydrogenation agents.
Abstract: The addition of a polyalkylmethacrylate having a weight average molecular weight of at least 600,000 has been found to be effective in reducing the pour point of a wax isomerate to a level that cannot be obtained with conventional pour point depressants. In a preferred embodiment, the wax isomerate is a slack wax isomerate.
Abstract: Hydrocarbon dewaxing using propane or other autorefrigerative dewaxing solvent can be practiced in a centrifuge wherein the centrifugal force generated in the centrifuge produces a pressure gradient permitting dewaxing to be practiced on a continuous basis.
Abstract: A two stage process for catalytically reforming a gasoline boiling range hydrocarbonaceous feedstock. The reforming is conducted in two stages wherein the first stage is operated in a fixed bed mode, and the second stage is operated in a moving bed continuous catalyst regeneration mode. A hydrogen-rich stream is recycled through both stages.