Recovery Or Purification Patents (Class 423/461)
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Patent number: 5698175Abstract: Disclosed is a process for purifying carbon nanotubes which has steps of 1) mixing carbon nanotubes which accompany carbon impurities with a reagent selected from a group consisting of oxidation agents, nitration agents and sulfonation agents in liquid phase, 2) reacting the carbon nanotubes with the reagent at a predetermined temperature in the liquid phase, wherein the carbon impurities except carbon nanotubes are selectively reacted to dissolve in the liquid phase, and 3) separating carbon nanotubes from which the impurities were released from the liquid phase then washing and drying it. A process for uncapping carbon nanotubes and a process for chemically modifying carbon nanotubes are also disclosed.Type: GrantFiled: July 3, 1995Date of Patent: December 16, 1997Assignee: NEC CorporationInventors: Hidefumi Hiura, Thomas Ebbesen
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Patent number: 5695734Abstract: A process for the isolation of carbon nanotubes from a mixture containing carbon nanotubes and graphite is disclosed, which includes the steps of:(a) reacting the mixture with a metal compound to intercalate the metal compound into the graphite;(b) reducing the reaction mixture obtained in step (a) to convert the intercalated metal compound to elemental metal;(c) heating the reduction mixture obtained in step (b) at a temperature of 450-600.degree. C. in an oxygen-containing atmosphere to selectively oxidize the graphite and the elemental metal; and(d) contacting the heated mixture obtained in step (c) with a liquid to dissolve the oxidized metal in the liquid and to separate the carbon nanotubes as a solid phase from the oxidized metal.Type: GrantFiled: September 15, 1995Date of Patent: December 9, 1997Assignee: Director-General of Agency of Industrial Science & TechnologyInventors: Fumikazu Ikazaki, Kunio Uchida, Motoo Yumura, Satoshi Ohshima, Yasunori Kuriki, Hiroshi Hayakawa
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Patent number: 5662876Abstract: A low-cost and facile method of purifying fullerenes to obtain a preparation enriched in a fullerene of selected molecular weight using activated carbon involves adding a fullarena mixture to the top end of a column comprising activated carbon, passing a solvent in which the selected molecular weight fullerene is soluble through the column, and recovering a fraction enriched in the selected molecular weight fullerene from the bottom end of the column. In addition to activated carbon, the column may further comprise silica gel, diatomaceous earth, or other materials which aid in column packing and eluent flow. The invention also provides for preparation of gram quantities of pure C.sub.60 and C.sub.70 fullerenes after a single column pass.Type: GrantFiled: May 5, 1994Date of Patent: September 2, 1997Assignee: University of South CarolinaInventors: James M. Tour, Walter A. Scrivens, Peter V. Bedworth
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Patent number: 5641466Abstract: A mixture of carbon nanotubes and impurity carbon materials, which include carbon nanoparticles and may possibly include amorphous carbon, is purified into carbon nanotubes of high purity by utilizing a significant difference in oxidizability between the nanotubes and the nanoparticles. The mixture is pulverized and heated in the presence of an oxidizing agent at a temperature in the range from 600.degree. to 1000.degree. C. until the impurity carbon materials are oxidized and dissipated into gas phase. The nanotubes remain almost unoxidized except for loss of some lengths from the tube tips. It is suitable to perform the heating in air or oxygen.Type: GrantFiled: June 2, 1994Date of Patent: June 24, 1997Assignee: NEC CorporationInventors: Thomas Ebbesen, Pulickel M. Ajayan, Hidefumi Hiura
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Patent number: 5587141Abstract: Soot containing fullerenes is produced by impressing a DC voltage between a carbonaceous anode and a cathode in an airtight chamber maintained in an inert gas atmosphere to cause arc discharge to occur. After termination of the impression of the DC voltage, an inert gas is blown into the chamber to fluidize the soot. The fluidized soot is discharged from the chamber and is brought into contact with a solvent to recover the fullerenes.Type: GrantFiled: February 13, 1995Date of Patent: December 24, 1996Assignee: Director-General of Industrial Science and TechnologyInventors: Satoshi Ohshima, Motoo Yumura, Yasunori Kuriki, Kunio Uchida, Fumikazu Ikazaki
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Patent number: 5560898Abstract: Carbon nanotubes are isolated from a mixture containing the carbon nanotubes and graphite particles by a process including the steps of:finely pulverizing the mixture;dispersing the pulverized product in a liquid medium;centrifuging the resulting dispersion to obtain a supernatant containing carbon nanotubes and graphite particles having a particle size of 0.3 .mu.m or less;separating the supernatant into a solid phase and a liquid phase; andcalcining the solid phase in an oxygen-containing atmosphere at a temperature sufficient to burn the graphite particles and to leave the nanotubes.Type: GrantFiled: August 1, 1994Date of Patent: October 1, 1996Assignee: Director-General of Agency of Industrial Science and TechnologyInventors: Kunio Uchida, Motoo Yumura, Satoshi Ohshima, Yasunori Kuriki, Kiyoshi Yase, Fumikazu Ikazaki
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Patent number: 5560892Abstract: A apparatus system is disclosed for time beneficiation of kish to produce coarse high purity graphite wherein a concentrate containing at least about 90% carbon is formed, treated with a dilute acid solution, and the pulp then subjected to an adjuvant-assisted attrition to form a novel synthetic flake graphite of 99+ wt. % carbon with at least 70% of the mass retained on +100 mesh, and an overall recovery of graphitic carbon from the feed of greater than 85% by weight.Type: GrantFiled: April 20, 1995Date of Patent: October 1, 1996Assignee: Indresco Inc.Inventors: George W. Bennett, Maxime Leduc, Jean-Guy St-Hilaire, Christian Garceau
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Patent number: 5424039Abstract: To produce active carbon particles by carbonizing a carbon based raw material in a steam atmosphere while feeding electricity to the raw material received in a rotary reactor, a plurality of electrical receiving rods are secured to the inner wall surface of a cylindrical wall of the rotary reactor in the equally-spaced relationship as seen in the circumferential direction. In operation, a certain intensity of electric current is fed to the electricity receiving rods via a plurality of electrodes and a plurality of electrode contacts to induce arc-discharging between the electricity receiving rods and the raw material received in the rotary reactor. To reliably prevent the temperature of the steam atmosphere from being abnormally elevated, carbon dioxide gas is introduced into a carbonizing chamber of the rotary reactor via a gas inflow pipe.Type: GrantFiled: June 24, 1994Date of Patent: June 13, 1995Assignee: Helyo Shoji Kabushiki KaishaInventor: Yoji Hiral
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Patent number: 5419889Abstract: A method for manufacturing a high purity graphite material comprises a baking process of a carbon material, a graphitizing process of the material and a highly purifying process of the material in sequential order, the highly purifying process of the material being carried out by high-frequency heating means under vacuum or reduced pressure. An apparatus for manufacturing a high purity graphite material comprises a container capable of being made vacuous or depressurized and in which an induction heating high-frequency coil and a graphite heater are incorporated, the container being provided with a gas discharge pipe and a gas supply pipe.Type: GrantFiled: April 14, 1994Date of Patent: May 30, 1995Assignee: Toyo Tanso Co., Ltd.Inventors: Tsuyoshi Matsumoto, Toru Hoshikawa
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Patent number: 5403365Abstract: A process for producing low mercury coal during precombustion procedures by releasing mercury through discriminating mild heating that minimizes other burdensome constituents. Said mercury is recovered from the overhead gases by selective removal.Type: GrantFiled: April 30, 1993Date of Patent: April 4, 1995Assignee: Western Research InstituteInventors: Norman W. Merriam, R. William Grimes, Robert E. Tweed
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Patent number: 5338529Abstract: Carbon clusters, such as C.sub.60 and C.sub.70 fullerenes are separated by means of a recognition selector having the formula: ##STR1## wherein R.sub.1 is ##STR2## wherein R.sub.2 is O, S or NR.sub.12 wherein R.sub.12 is independently hydrogen or P.dbd.O with the proviso that when R.sub.12 is P.dbd.O, then only one such group is present and all R.sub.2 's are additionally bonded to R.sub.12,R.sub.4 is independently O, S or NH,R.sub.3 and R.sub.5 are each independently hydrogen or lower alkyl,n and o are each independently zero, 1, 2 or 3,p, q, r, s and t are each independently zero or 1,Ar is a monocyclic or ortho-fused polycyclic aromatic moiety having up to 10 carbon atoms, either of which may be unsubstituted or substituted with one or more lower alkyl, NO.sub.2, N(R.sub.6).sub.3.sup.+, CN, COOR.sub.7, SO.sub.3 H, COR.sub.8 and OR.sub.9 wherein R.sub.6, R.sub.7, R.sub.8 and R.sub.9 are each independently hydrogen or lower alkyl;W is H or CH.dbd.CH.sub.2 ; andm is 1 to 10.Type: GrantFiled: April 27, 1992Date of Patent: August 16, 1994Assignee: Research Corporation Technologies, Inc.Inventors: William H. Pirkle, Christopher J. Welch
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Patent number: 5316471Abstract: An apparatus for improving mass transfer in a multiple hearth furnace has a plurality of risers adjacent the furnace center shaft which are in fluid communication with a source of treatment fluid. The risers have radially extending branch pipes, each pipe having a plurality of downcomers corresponding to the rabbles on an adjacent rabble arm. The downcomers have outlets or nozzles at their distal ends and they are preferably located adjacent a rear face of the rabble, near a trailing edge. In operation, as the rabbles plough over the material on the furnace hearth, the downcomers inject a treatment fluid, such as steam or reducing gas, into the material at the point of stirring. This ensures full exposure of the material to the treatment fluid. A second embodiment places the outlets beneath the top surface of the material to be treated. A method for mass transfer on a rotary hearth furnace is also disclosed.Type: GrantFiled: February 16, 1993Date of Patent: May 31, 1994Inventor: David J. Nell
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Patent number: 5310532Abstract: A low-cost and facile method of purifying fullerenes to obtain a preparation enriched in a fullerene of selected molecular weight using activated carbon involves adding a fullerene mixture to the top end of a column comprising activated carbon, passing a solvent in which the selected molecular weight fullerene is soluble through the column, and recovering a fraction enriched in the selected molecular weight fullerene from the bottom end of the column. In addition to activated carbon, the column may further comprise silica gel, diatomaceous earth, or other materials which aid in column packing and eluent flow.Type: GrantFiled: June 10, 1992Date of Patent: May 10, 1994Assignee: University of South CarolinaInventors: James M. Tour, Walter A. Scrivens, Peter V. Bedworth
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Patent number: 5281406Abstract: A process has been developed to effectively separate and recover essentially pure amounts of both C.sub.60 and C.sub.70 from carbon soot and higher molecular weight fullerenes. This process first extracts the fullerenes from carbon soot and then sequentially separates the C.sub.60 and C.sub.70 molecules using high performance or low pressure adsorption chromatography packed column containing a gel polymer having aromaticity and a pore size ranging from 10 to 500 .ANG..In this process, a first stage of fractionation of the fullerenes is preferably accomplished by selective supercritical fluid extraction (SFE) of C.sub.60. Unrecovered C.sub.60 and C.sub.70 molecules are then extracted by supercritical fluid extraction at a higher pressure and/or higher temperature.Type: GrantFiled: April 22, 1992Date of Patent: January 25, 1994Assignee: Analytical Bio-Chemistry Laboratories, Inc.Inventors: David L. Stalling, Said Saim, Congyuan Guo, Kenneth Kuo
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Patent number: 5229099Abstract: Commercially valuable chemicals are extracted from tire-derived pyrolytic oils by subjecting the pyrolytic oils to a fractional distillation at a temperature of up to about 204.degree. C. under atmospheric pressure to isolate at least one commercially valuable chemical selected from the group consisting of paraffins, naphthenes, olefins and aromatics. Particularly valuable chemicals which can be extracted from tire-derived pyrolytic oils are benzene, toluene, xylene, styrene and limonene-dl. The distillation fraction boiling above 204.degree. C. can be used as an extension oil in the manufacture of various rubber and plastic parts. Also disclosed is an improved process for producing carbon black by vacuum pyrolysis of used rubber tires.Type: GrantFiled: November 4, 1991Date of Patent: July 20, 1993Assignee: Universite LavalInventor: Christian Roy
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Patent number: 5188809Abstract: A process for separating a feed mixture of zirconium and petroleum coke containing traces amount of radioative materials by flotation process utilizing a plurality of flotation cells. The process comprises grinding the feed mixture, slurrying the ground feed mixture with water, treating the slurry with a flotation agent and a collector for the coke and subjecting the treated slurry to air sparging and agitation to create an overflow and an underflow. The overflow is then filtered to collect substantially zircon-free coke for further processing.Type: GrantFiled: August 31, 1990Date of Patent: February 23, 1993Assignee: Teledyne Industries, Inc.Inventors: William A. Crocker, John C. Haygarth, Jon A. Riesen, John R. Peterson
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Patent number: 5183529Abstract: Method of fabricating free-standing diamond films by depositing and adhering polycrystalline diamond by hot filament chemical vapor deposition (1-100 Torr, filament temperature equal to or greater than 1900.degree. C., substrate temperature of 650.degree.-950.degree. C.) onto a substrate meltable at a temperature slightly in excess of the deposition temperature; and (b) prior to cooling said polycrystalline diamond particles, increasing (50.degree.-300.degree. C.) the substrate temperature to melt at least a portion thereof while permitting such melt to emigrate from the diamond films.Type: GrantFiled: October 29, 1990Date of Patent: February 2, 1993Assignee: Ford Motor CompanyInventors: Timothy J. Potter, Michael A. Tamor, Ching-Hsong Wu
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Patent number: 5087436Abstract: Commercially valuable chemicals are extracted from tire-derived pyrolytic oils by subjecting the pyrolytic oils to a fractional distillation at a temperature of up to about 204.degree. C. under atmospheric pressure to isolate at least one commercially valuable chemical selected from the group consisting of paraffins, naphthenes, olefins and aromatics. Particularly valuable chemicals which can be extracted from tire-derived pyrolytic oils are benene, toluene, xylene, styrene and limonene-dl. The distillation fraction boiling above 204.degree. C. can be used as an extension oil in the manufacture of various rubber and plastic parts. Also disclosed is an improved process for producing carbon black by vacuum pyrolysis of used rubber tires.Type: GrantFiled: July 17, 1990Date of Patent: February 11, 1992Assignee: Universite LavalInventor: Christian Roy
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Patent number: 5085738Abstract: An apparatus for the thermal conversion and recovery of organic waste materials includes an oxygen-free chamber filled with molten lead and a method of use of the apparatus. The chamber is elongate and inclined so that organic material introduced in a lower portion of the chamber migrates through the molten lead to a higher portion of the chamber due to the organic material having a specific gravity less than that of lead. As the organic material migrates through the molten lead, the material is thermally converted to gaseous and vapor hydrocarbons that are captured in a condenser. The gaseous hydrocarbons are utilized to heat the lead in the chamber and the vapor is condensed to liquid hydrocarbons in the condenser. Residual solids flow to a reservoir connected to the chamber. Light carbon black is drawn into a receiver by a vacuum line located near the top of the reservoir and all other residual solids flow over a reservoir wall.Type: GrantFiled: May 7, 1990Date of Patent: February 4, 1992Inventors: Windel L. Harris, James R. Donnohue
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Patent number: 5071515Abstract: The density and crush resistance of calcined coke are improved by depositing coker feedstock on green (uncalcined) coke, thereafter subjecting the coke to a heat soak and then calcining the coke.Type: GrantFiled: September 28, 1989Date of Patent: December 10, 1991Assignee: Conoco Inc.Inventors: Bruce A. Newman, Lynn J. Whitebay
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Patent number: 5037628Abstract: A method for reclaiming carbon black from scrap rubber material including the following steps. The scrap rubber material is first pyrolyzed to produce a char material that contains a mixture of agglomerated or cluster particles which consist of agglomerations of finer carbon black particles and unitary grit like particles. The agglomerated particles are then selectively de-agglomerated by agitation of the char material into the finite component particles of carbon black. These finite component particles are then separated from the unitary particles to obtain a final carbon black which is comparable to commerical grade carbon blacks.Type: GrantFiled: November 7, 1990Date of Patent: August 6, 1991Assignee: American Tire Reclamation, Inc.Inventor: John H. Fader
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Patent number: 4978650Abstract: An activated carbon sorbent in which oxygen has been substantially removed from said carbon by outgassing and said oxygen has been replaced by subsequent reaction of the outgassed carbon with a passivating substance.Type: GrantFiled: August 15, 1988Date of Patent: December 18, 1990Assignee: SymBiotech IncorporatedInventors: Robert W. Coughlin, Edward M. Davis
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Patent number: 4973464Abstract: A process for the treatment of ground, spent potlinings generated during the production of metallic aluminum to reduce cyanide content to environmentally nonhazardous levels. Potlinings are ground or otherwise suitably reduced in size to a particle size of not greater than about 2 inches in any dimension and roasted in a stream of air or nitrogen at a temperature between about 500.degree. F. and 1400.degree. F. Roasting for an appropriate time-temperature interval reduces cyanide content to desired levels without combustion of a major portion of carbonaceous material, resulting in an end product rich in carbon and fluorine which may be salable because of this content.Type: GrantFiled: February 21, 1989Date of Patent: November 27, 1990Assignee: Ogden Environmental ServicesInventor: William S. Rickman
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Patent number: 4957721Abstract: A method and apparatus for reactivating spent granular activated carbon is the subject of this invention. The carbonaceous material is to be activated is fed to a drying zone where it is dried until incoming air and recycle gases fluidize the drying zone thus causing the dried material to be pneumatically conveyed to the regeneration or activation zone. In this zone, the temperature is raised to effect the oxidizing reactions thereby volatilizing at least some of the contaminants while converting residual carbon to carbon monoxide and hydrogen. Some of the produce gases from the drying and regeneration zones are utilized to fluidize both of these zones and the remaining gases are directed to the afterburner where combustibles are consumed. The product gases from the afterburner are then directed to a conditioning zone where combustible fuel is introduced so as to consume any residual oxygen.Type: GrantFiled: June 28, 1988Date of Patent: September 18, 1990Inventors: Jack J. Lonsinger, Deborah A. Lonsinger
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Patent number: 4957722Abstract: A process for producing chlorides by the chlorination of a material selected from the group consisting of aluminous materials and metal and metalloid oxides in the presence of a reductant. The method comprises calcining a carbonaceous material with added steam to oxidize substantially all precursors of chlorinated hydrocarbons and to form a reductant; and chlorinating a material selected from the group consisting of aluminous materials and metal oxides in the presence of the reductant.Type: GrantFiled: April 3, 1989Date of Patent: September 18, 1990Assignee: Aluminum Company of AmericaInventors: Raouf O. Loutfy, Kirk R. Weisbrod, James C. Withers
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Patent number: 4956259Abstract: A toner composition having particles substantially in the spherical form and comprises a binder resin and carbon black having a number-average particle size of 20 to 500 millimicrons and a standard deviation of particle size distribution of 70 millimicrons or smaller.Type: GrantFiled: July 14, 1987Date of Patent: September 11, 1990Assignee: Kao CorporationInventors: Yoshitsugu Shirasaki, Yoshiaki Torimoto
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Patent number: 4947929Abstract: A heat exchanger for heating fluid particulate material comprising a heating chamber, heating means associated with the heating chamber, a hopper mounted above the heating chamber, a delivery chamber located below the heating chamber, a set of flow passageways extending through the heating chamber between the hopper and delivery chamber, said delivery chamber having an outlet at its lower portion.Type: GrantFiled: March 25, 1987Date of Patent: August 14, 1990Inventor: Peter J. Stewart
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Patent number: 4946663Abstract: High surface are carbon fibers are produced by heating carbon fibres in the presence of a quality of alkali metal hydroxide in excess of 50% by weight based on weight of carbon at temperatures of above 500.degree. C. in an inert atmosphere.Type: GrantFiled: October 14, 1988Date of Patent: August 7, 1990Assignee: The British Petroleum Company, p.l.c.Inventors: Gary J. Audley, Alan Grint
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Patent number: 4894122Abstract: A process for the desulphurization of residuals of petroleum distillation in the form of coke particles having an initial sulphur content greater than about 5% by weight. Desulphurization is effected by means of a continuous electrothermal process based on a plurality of sequentially connected fluidized beds into which the coke particles are successively introduced. The necessary heat generation to desulphurize the coke particles is obtained by using the coke particles as an electrical resistance in each fluidized bed by providing a pair of electrodes that extend into the fluidized coke particles and passing an electrical current through the electrodes and through the fluidized coke particles. A last fluidized bed without electrodes is provided for cooling the desulphurized coke particles after the sulphur level has been reduced to less than about 1% by weight.Type: GrantFiled: January 17, 1989Date of Patent: January 16, 1990Assignee: Instituto Mexicano de Investigaciones SiderurgicasInventors: Arturo Lazcano-Navarro, Andres Geronimo-Torres
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Patent number: 4894144Abstract: A virgin heavy oil is hydrotreated, separated into a light fraction and a heavy fraction which are separately delay coked to obtain (a) a coke product of low sulfur content suitable for use as recarburizer coke or for use in the manufacture of graphite electrodes used in the manufacture of steel and (b) a coke product of higher sulfur content suitable for use in electrodes employed in the manufacture of aluminum.Type: GrantFiled: November 23, 1988Date of Patent: January 16, 1990Assignee: Conoco Inc.Inventors: Bruce A. Newman, Bharat S. Chahar
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Patent number: 4889695Abstract: Disclosed in a process for recovering aluminum flouride, caustic, and carbon from spent potlining retrieved from an aluminum electrolytic reduction cell. Spent potlining is treated by leaching with a caustic solution to produce a fluoride-rich basic liquor and carbonaceous solid residue followed by contacting the carbonaceous solid with an acid bath of aluminum sulfate and sulfuric acid to produce a fluoride-rich acid liquor.Type: GrantFiled: February 20, 1985Date of Patent: December 26, 1989Assignee: Aluminum Company of AmericaInventor: J. Finley Bush
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Patent number: 4888029Abstract: A process for desulfurizing carbonaceous material containing inorganic bound sulfur, organic bound sulfur, or conbinations thereof. The process comprises reacting the carbonaceous material at desulfurization conditions with a hydrogen source material in the presence of a reaction accelerator to enhance production and reactivity of atomic hydrogen supplied by the hydrogen source. The reaction is prefereably carried out in the presence of a flowing reaction medium which carries away hydrogen sulfide products and other volatile desulfurization products separating them from the carbonaceous material.Type: GrantFiled: June 7, 1988Date of Patent: December 19, 1989Assignees: The Board of Trustees of Southern Illinois University, The Illinois State Geological SurveyInventors: Richard H. Shiley, Randall E. Hughes, John R. Webster, Conrad C. Hinckley, Gerald V. Smith, Tomasz Wiltowski
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Patent number: 4859212Abstract: Pretreatment of coal by devolatization at temperatures ranging from about 420.degree. C. to about 450.degree. C. for from about 10 minutes to about 30 minutes before leaching with molten caustic leads to a significant reduction in carbonate formation, greatly reducing the cost of cleaning coal on a per ton basis.Type: GrantFiled: September 15, 1988Date of Patent: August 22, 1989Assignee: Iowa State University Research Foundation, Inc.Inventors: Colin D. Chriswell, Surender M. Kaushik, Navin D. Shah, Richard Markuszewski
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Patent number: 4847063Abstract: Method of forming a hollow, carbon/carbon composite article around an axis of symmetry, in which method a heat refractory mandrel is shaped to provide a desired inner surface configuration and tolerances of the article, and one or more plies of thermally stable carbon filaments are braided over the surface of the mandrel. The filaments have a diameter of substantially not greater than about 6 microns and a modulus of elasticity of substantially not less than about 45.times.10.sup.6 psi. The plies are then impregnated with a carbonizable liquid impregnant, and the assembly of impregnated plies and mandrel is heat treated so as to carbonize the impregnant. The resulting composite article has a high translation of the original strength of the filaments and has an inner surface defined by the outer surface of the mandrel.Type: GrantFiled: December 2, 1987Date of Patent: July 11, 1989Assignee: Fiber Materials, Inc.Inventor: Jack B. Smith
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Patent number: 4836998Abstract: A process for producing an improved solid carbon reductant, which contains relatively low amounts of residual hydrocarbons and a high surface area. This improved reductant is produced by a method comprising heating carbonaceous material, such as petroleum coke, with steam in either reducing or oxidizing atmosphere to a temperature of from about 650.degree. C. to about 1150.degree. C. Using the improved reductant during chlorination of aluminous materials and metal or metalloid oxides will result in reducing the level of chlorinated hydrocarbon (C.sub.x Cl.sub.y) production due to residual hydrogen and/or hydrocarbons.Type: GrantFiled: December 21, 1984Date of Patent: June 6, 1989Assignee: Aluminum Company of AmericaInventors: Raouf O. Loutfy, Kirk R. Weisbrod
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Patent number: 4822765Abstract: Activated carbon, useful in a pharmaceutical composition for adsorbing exogenous or endogenous toxins from the gastrointestinal tract of a patient can be prepared by a process including a step of treating activated carbon with an aqueous ammonia solution to provide a resultant activated carbon having a pH of 6 to 8.Type: GrantFiled: May 8, 1987Date of Patent: April 18, 1989Assignee: Kureha Kagaku Kogyo Kabushiki KaishaInventor: Yasushi Nishimura
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Patent number: 4816122Abstract: Fluoride-containing wastes, arising in the aluminium industry, particularly spent cell linings from reduction cells, are digested with caustic soda for conversion of sodium cryolite to NaF.By use of very strong caustic soda NaF may be left in the solid residues after removal of the residual liquor and recovered from such residues by water leaching.As an alternative weaker caustic soda may be used in the digestion stage and subsequently be crystallised out from the residual liquor, after separation from the solid residues, by evaporating and/or cooling the liquor. The precipitated NaF is then conventiently redissolved in water.The NaF solution prepared by either route is then preferably subjected to electrodialysis to recover a solution of HF from it. Such HF is conveniently converted to AlF.sub.3 by reaction with alumina.Type: GrantFiled: September 13, 1985Date of Patent: March 28, 1989Assignee: Alcan International LimitedInventor: Gordon Lever
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Patent number: 4814157Abstract: Disclosed are polyacrylonitrile carbon fibers excellent in substrate strength and adhesion to matrix resin wherein average nitrogen content in the whole carbon fibers which is measured by elementary analysis is 0.5-4.5% by weight and average nitrogen concentration (N/C atom number ratio) in the whole carbon fibers which is measured by elementary analysis and surface silicon concentration (Si.sub.2p /C.sub.1s atom number ratio), surface nitrogen concentration (N.sub.1s /C.sub.1s atom number ratio) and surface oxygen concentration (O.sub.1s /C.sub.1s atom number ratio) which are measured by X-ray photoelectron spectroscopy satisfy the following formulas:0.ltoreq.Si.sub.2p /C.sub.1s .ltoreq.0.020.67 N/C+0.08.ltoreq.O.sub.1s /C.sub.1s -2 Si.sub.2p /C.sub.1s .ltoreq.0.40.ltoreq.N.sub.1s /C.sub.1s -N/C.ltoreq.0.04and method for producing the carbon fibers.Type: GrantFiled: February 9, 1987Date of Patent: March 21, 1989Assignee: Mitsubishi Rayon Co., Ltd.Inventors: Hirofumi Uno, Hajime Asai, Fujio Nakao
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Patent number: 4804390Abstract: A process for removing mineral impurities such as metal oxides from coal and shale oil structures is disclosed. The process is carried out by subjecting crushed coal or shale to a hydrocarbon fluoride leaching solution, separating the HF leach liquor from the coal or shale, washing the coal or shale with water, leaching the washed coal or shale with hydrogen chloride solution, separating the HCl leach liquor from the coal or shale, washing the coal or shale with water, and removing residual impurities from the treated coal or shale by heating under a vacuum. The process allows for the recovery of carbons and hydrocarbons of high purity from coal or shale which do not require expensive emission control equipment when combusted.Type: GrantFiled: July 30, 1984Date of Patent: February 14, 1989Inventors: Robert Lloyd, Maxwell J. Turner
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Patent number: 4780112Abstract: A process for treating carbon to reduce the ash content therein. The process involves treating the carbon with a fluorine acid solution which consists of an aqueous solution of hydrofluorosilicic acid and hydrogen fluoride, such that the available metal oxides are converted to metal fluorides and/or metal fluorosilicates and separating the treated carbon from the metal fluorides and/or metal fluorosilicates produced by the treatment.Type: GrantFiled: December 10, 1986Date of Patent: October 25, 1988Assignee: Oabrand PTY. LimitedInventors: Robert Lloyd, Maxwell J. Turner
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Patent number: 4770867Abstract: The invention concerns a process for the production of vapor-deposited carbon fibres wherein a gaseous or vaporized hydrocarbon which is entrained by a carrier gas is pyrolyzed on a substrate in a flow reactor at a temperature of between 950.degree. and 1300.degree. C. in two successive stages, a germination stage and a growth stage.The process comprises the following steps:preparing a gaseous mixture comprising from 50 to 90% and preferably from 85 to 65% by volume of hydrogen and/or helium and from 10 to 40% and preferably from 15 to 35% by volume of methane;circulating the mixture in the reactor over a substrate comprising from 10.sup.-8 to 10.sup.-4 g/cm.sup.2 of a catalyst selected from iron, nickel, cobalt and alloys thereof;initiating germination and growth of the carbon fibres in respect of length at a temperature t1 which is stabilized at between 950.degree. and 1050.degree. C.Type: GrantFiled: January 9, 1986Date of Patent: September 13, 1988Assignee: Le Carbone-LorraineInventors: Michel Coulon, Najib Kandani, Lucien Bonnetain, Jacques Maire
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Patent number: 4769359Abstract: A process for the production of active carbon by treating a carbonaceous feed with a mixture of KOH and NaOH in a molar ration of NaOH:KOH of 80:20 to 20:80 and heating to at least 500.degree. C. in an inert atmosphere.Type: GrantFiled: April 21, 1987Date of Patent: September 6, 1988Assignee: The British Petroleum Company p.l.c.Inventors: Gary J. Audley, Keith A. Holder
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Patent number: 4756898Abstract: Machinable and structurally stable, low density microcellular carbon, and catalytically impregnated carbon, foams, and process for their preparation, are provided. Pulverized sodium chloride is classified to improve particle size uniformity, and the classified particles may be further mixed with a catalyst material. The particles are cold pressed into a compact having internal pores, and then sintered. The sintered compact is immersed and then submerged in a phenolic polymer solution to uniformly fill the pores of the compact with phenolic polymer. The compact is then heated to pyrolyze the phenolic polymer into carbon in the form of a foam. Then the sodium chloride of the compact is leached away with water, and the remaining product is freeze dried to provide the carbon, or catalytically impregnated carbon, foam.Type: GrantFiled: April 30, 1987Date of Patent: July 12, 1988Assignee: The United States of America as represented by the United States Department of EnergyInventors: Robert W. Hopper, Richard W. Pekala
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Patent number: 4741741Abstract: Chemical beneficiation of coal and other carbonaceous solids utilizing hydrofluoric acid and ammonium chloride.Type: GrantFiled: October 17, 1986Date of Patent: May 3, 1988Assignee: The Standard Oil CompanyInventors: George F. Salem, Angela M. Schmidt
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Patent number: 4742040Abstract: A process for manufacturing a carbon molecular sieve having both increased gas adsorption capacity and selectivity, which entails:(a) adding coal tar, coal tar pitch, or a combination thereof to powdered coconut shell charcoal as a binder;(b) pelletizing the mixture and carbonizing the same at about 600.degree.-900.degree.;(c) immersing the pellets in mineral acid solution, thereby sustantially removing soluble ingredients containing alkaline metal compounds therefrom;(d) drying the immersed pellets;(e) adding to the dried pellets a fraction of cresote which is distilled at a temperature of 140.degree. to 260.degree. C., in an amount sufficient to increase both said gas adsorption capacity and selectivity;(f) heating the pellets to about 600.degree.-900.degree. C., for about 10-60 minutes; and(g) cooling the pellets in an inert gas.Type: GrantFiled: January 29, 1987Date of Patent: May 3, 1988Assignee: Kuraray Chemical Co., Ltd.Inventors: Takushi Ohsaki, Susumu Abe
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Patent number: 4738753Abstract: The method employs a furnace, wherein organic distillation products released from the binder and the gaseous and particulate decomposition products are burned off. Bodies, placed on the ceramic bottom plate of a truck, are introduced into the pre-heating zone of the furnace, covered with protective coverings, and heated to 200.degree.-600.degree. C. in an oxidizing medium. Thereafter, the coverings are removed in a vestibule, in an inert or slightly reducing medium, and the bodies are introduced into the calcining zone, provided with an inert or slightly reducing medium, to be further heated up to a temperature in the 1000.degree. to 1200.degree. C. range. Lastly, the bodies are cooled in a first cooling zone down to 400.degree.-450.degree. C. in an inert or slightly reducing medium, and in a second zone down to room temperature.Type: GrantFiled: September 23, 1985Date of Patent: April 19, 1988Assignees: Alusuisse Italia S.p.A, Italimpianti Societa Italiana Impianti p.A., Sirma S.p.A.Inventors: Renzo Corato, Giulio Ganapini, Hans-Anton Meier, Mauro Poggi, Antonio Rosso, Sergio Sanchioni
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Patent number: 4725423Abstract: A process and apparatus for the regeneration of shaped carbon, and especially graphite, bodies used in the presence of molten silicon. The shaped bodies are heated in an inert atmosphere to a temperature in the range of from 1700.degree. to 3000.degree. C. and maintained at this temperature for a defined period of time. The process substantially prolongs the service life of the shaped bodies. The apparatus includes at least one evacuable loading chamber, and evacuable heatable heating chamber connected to the loading chamber and an evacuable coolable cooling chamber connected to the heating chamber. A support capable of moving between the loading, heating and cooling chambers is adpated for receiving the shaped bodies to be regenerated.Type: GrantFiled: February 6, 1986Date of Patent: February 16, 1988Assignee: Wacker-Chemitronic Gesellschaft fur Elektronik-Grundstoffe mbHInventors: Adalbert Ellbrunner, Georg Priewasser, Horst Stock
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Patent number: 4705531Abstract: A coal or similar carbonaceous fuel is selectively freed of sodium by water washing it and ion exchanging the washed coal with a strong aqueous electrolyte solution which is substantially free of sodium ions and contains a kind and concentration of ions which are correlated with the composition of the coal to cause a selective removal of ion-exchangeable sodium from the coal, with at least a significant proportion of the ion-exchanging being conducted within a pipeline.Type: GrantFiled: September 24, 1985Date of Patent: November 10, 1987Assignee: Shell Oil CompanyInventor: George C. Blytas
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Patent number: H478Abstract: A coal or similar carbonaceous fuel is selectively freed of sodium by water washing it and ion exchanging the washed coal with a strong aqueous electrolyte solution which is substantially free of sodium ions and contains a kind and concentration of ions which are correlated with the composition of the coal to cause a selective removal of ion-exchangeable sodium from the coal.Type: GrantFiled: September 24, 1985Date of Patent: June 7, 1988Assignee: Shell Oil CompanyInventor: George C. Blytas
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Patent number: H1074Abstract: The separation of cationic materials from an ore body is assisted by the application of an electric potential, and resulting current, to the ore body, in association with iron or sulphur oxidizing bacteria. The combined process induces migration of cationic metals to a cathode suspended within the ore body so that the cationic metal can be preferentially separated from the ore body.Type: GrantFiled: February 27, 1990Date of Patent: July 7, 1992Assignee: The United States of America as represented by the United States Department of EnergyInventors: Norman Lazaroff, Patrick R. Dugan