By Oxidizing Hydroquinone Or Anthraquinone Patents (Class 423/588)
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Patent number: 5127963Abstract: A novel chemical extraction/washing process is described for detoxifying lead contaminated materials, and in particular, for detoxifying broken lead/acid storage battery casings made from ebonite. In particular, the preferred process of the invention enables the lead content of broken ebonite battery casing material to be reduced to the point that the processed ebonite is no longer a potential harzardous waste by any EPA definition. In the preferred embodiment, the novel process of the invention makes use of the chemical leaching capabilities of nitric acid, and the water solubility of lead nitrates, to dissolve and then wash away the combined lead compounds that contaminate and render hazardous broken ebonite battyer casing material, leaving a clean and usable ebonite product for recycling.Type: GrantFiled: March 21, 1991Date of Patent: July 7, 1992Assignee: Rubber Recycling, Inc.Inventors: George R. Hartup, Jack E. Leonard
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Patent number: 5120524Abstract: A process for co-producing hydrogen peroxide and another useful product, namely either an oxalate ester or a carbonate ester product, is provided. The process comprises reacting a saturated monohydric alcohol with carbon monoxide and a quinone to form an oxalate ester or a carbonate ester product and hydroquinone. The hydroquinone is then reacted with oxygen to form hydrogen peroxide and a quinone. The quinone from the second reaction can be recycled to the alcohol-carbon monoxide first reaction.Type: GrantFiled: July 18, 1991Date of Patent: June 9, 1992Assignee: Kerr-McGee CorporationInventor: Paul C. Ellgen
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Patent number: 5114701Abstract: The invention concerns a method for producing hydrogen peroxide using a process based on anthraquinone derivatives. According to the invention the solvent system of the working solution in said process contains carbamate having a general formula ##STR1## where groups R.sup.1 and R.sup.2, which can be the same or different ones, are a hydrogen atom or a hydrocarbon group and R.sup.3 is a hydrocarbon group,whereby the groups R.sup.1, R.sup.2 and R.sup.3 can optionally be part of a cyclic structure and/or substituted by groups which are inert to the process.Type: GrantFiled: August 22, 1990Date of Patent: May 19, 1992Assignee: Kemira OYInventors: Elias Suokas, Reijo Aksela
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Patent number: 5071634Abstract: The invention relates to a process for the production of hydrogen peroxide by the anthraquinone process. A reaction mixture into which there are fed hydrogen or a hydrogen-containing gas and a working solution, i.e. an anthraquinone derivative in an organic solvent, is circulated via a tubular static mixing zone (9) which is continuous or comprises several parts, in order to hydrogenate the anthraquinone derivative in the presence of a solid catalyst, and by removing hydrogenated working solution (13) and gas (11) from the circulating reaction mixture (8). According to the invention, the reaction mixture (14) is circulated (8) via a catalyst-coated static mixing zone (9), where it is simultaneously both mixed and catalyzed.Type: GrantFiled: January 24, 1990Date of Patent: December 10, 1991Assignee: Kemira OyInventors: Teuvo Maunula, Eva-Liisa Mustonen, Ilkka Turunen, Pirkko Virta
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Patent number: 5063043Abstract: The invention relates to a process in the continuous catalytic hydrogenation step during production of hydrogen peroxide according to the anthraquinone process by alternate reduction and oxidation of a working soloution of alkylated anthraquinones, said working solution being supplied at the upper end of the hydrogenation reactor and uniformly distributed across the surface of the monolithic catalyst bed, while simultaneously introducing hydrogen gas or hydrogen gas-containing gas, the flow of said working solution through the catalyst bed being adjusted such that the liquid flow is lower than the falling rate of the liquid through the bed, whereby gas bubbles are formed which have a diameter close to the diameter of the catalyst channels, and whereby such gas plugs and corresponding liquid plugs alternately and automatically flow downwardly through said channels and a so-called plug flow is obtained.Type: GrantFiled: February 23, 1990Date of Patent: November 5, 1991Assignee: Eka Nobel ABInventor: Erik A. Bengtsson
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Patent number: 4824609Abstract: A process is provided to remove inert contaminants from a working compound employed for the manufacture of hydrogen peroxide by the reduction and oxidation of a solution of alkylated anthraquinones and derivatives. The contaminants are removed by the process of contacting the working compound, a solvent, and carbon dioxide to form a first portion and a residue portion, separating the two portions and recovering the purified working solution from the first portion.Type: GrantFiled: January 7, 1988Date of Patent: April 25, 1989Assignee: FMC CorporationInventor: Dalbir S. Sethi
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Patent number: 4803063Abstract: A process for the cyclic production of hydrogen peroxide comprising alternating the reduction of oxidation of a quinone in a solvent medium and extracting the hydrogen peroxide. The solvent medium contains a carboxylic acid amide comprising at least one aryl group to satisfy one of the following conditions:(a) an aryl group is attached to the nitrogen or the carbon of the carbonyl; or(b) an aryl group is attached to the nitrogen and another aryl group, which is the same or different, is attached to the nitrogen or to the carbon of the carbonyl.Type: GrantFiled: April 1, 1988Date of Patent: February 7, 1989Assignees: Atochem, OxysyntheseInventor: Christian Pralus
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Patent number: 4800074Abstract: A process for the production of hydrogen peroxide according to the anthraquinone process. According to the process certain cyclic urea derivatives are used as solvents, and particularly as solvents for anthrahydroquinones. The cyclic urea derivatives whcih can be N,N'-dialkyl substituted alkyleneurea, give a very good solubility for anthrahydroquinones and also for anthraquinones. The compounds can be used as the sole solvent at the production of hydrogen peroxide or in combination with conventionally used solvents such as hydrocarbons.Type: GrantFiled: March 21, 1988Date of Patent: January 24, 1989Assignee: EKA Nobel ABInventors: Erik Bengtsson, Ulf Andersson
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Patent number: 4800073Abstract: A process for the production of hydrogen peroxide according to the anthraquinone process. According to the process certain alkyl substituted caprolactames are used as solvents, and particularly as solvents for anthrahydroquinones. The substituted caprolactames, which for example can be hexyl caprolactam and octyl caprolactam, give a very good solubility for anthrahydroquinones and also for anthraquinones. The compounds can be used as the sole solvent at the production of hydrogen peroxide or in combination with conventionally used solvents such as hydrocarbons.Type: GrantFiled: March 21, 1988Date of Patent: January 24, 1989Assignee: EKA Nobel ABInventors: Erik Bengtsson, Ulf Andersson
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Patent number: 4800075Abstract: An improved fixed-bed cyclic anthraquinone process for production of hydrogen peroxide wherein the improvement is using a hydrogenation catalyst comprising palladium or a mixture of palladium and platinum on a support containing alpha alumina. The preferred range of palladium is 0.1 to 3 weight percent and the preferred range of platinum, when present, is greater than 0.01 weight percent (based on the total weight of the catalyst). The preferred catalyst support contains greater than 5 percent alpha alumina.Type: GrantFiled: December 14, 1987Date of Patent: January 24, 1989Assignee: E. I. Du Pont de Nemours and CompanyInventor: Colie L. Jenkins
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Patent number: 4759921Abstract: An aqueous hydrogen peroxide extract which contains small amounts of dispersed working solution and a working solution which contains small amounts of dispersed aqueous hydrogen peroxide are collected in the extraction stage of the anthraquinone method for preparing hydrogen peroxide. In order to purify these solutions, the working solution is compounded with aqueous hydrogen peroxide or preferably with water and the hydrogen peroxide extract is compounded with an organic dissolving mixture, preferably a quinone dissolver, and the respective dispersed phase is separated out with the aid of coalescers in a separator unit. It is especially preferable to add 1-3% by volume water or 1-3% quinone dissolver before the coalescer stages and to use coalescers with a drop-enlarging design and filter layers consisting of thermally desized glass filament yarn.Type: GrantFiled: October 1, 1987Date of Patent: July 26, 1988Assignee: Degussa AGInventors: Wolfgang Kunkel, Gustaaf Goor, Jorg Kemnade
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Patent number: 4668436Abstract: A process is provided to regenerate and purify a working solution for the manufacture of hydrogen peroxide by the reduction and oxidation of a solution of alkylated anthraquinones and derivatives. The regeneration and purification is effected by removing inerts by contacting the working solution and an noncyclic hydrocarbon to form a liquid first phase and a second phase, separating the two phases and recovering both the noncyclic hydrocarbon and the purified working solution by distillation.Type: GrantFiled: December 13, 1985Date of Patent: May 26, 1987Assignee: FMC CorporationInventor: Dalbir S. Sethi
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Patent number: 4668499Abstract: The invention is an improvement to the cyclic anthraquinone process for making hydrogen peroxide comprising the addition of catalytically effective amounts of an additive to reoxidize inert quinone-degradation species to useful quinones. The additive comprises aromatic tertiary amines having an aqueous pK.sub.a value of about 4 to 9 and the general formula ##STR1## wherein R.sub.1 is a substituted or unsubstituted phenyl group and R.sub.2 and R.sub.3 are the same or different alkyl groups containing 1 to 18 carbon atoms.Type: GrantFiled: January 27, 1986Date of Patent: May 26, 1987Assignee: E. I. Du Pont de Nemours and CompanyInventor: John D. Rushmere
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Patent number: 4606905Abstract: A cyclic process for hydrogen peroxide production comprises a reduction of a quinone compound, followed by an oxidation into hydroperoxide, then finally a water extraction giving an aqueous hydrogen peroxide solution. An aqueous solution containing an organophosphonic acid, such as diethylene triamino pentamethylenephosphonic acid, and optionally associated with nitric acid or a nitrate is introduced during the oxidation and extraction phases to reduce the corrosion during the oxidation and extraction phases and improve the oxidation yield.Type: GrantFiled: January 7, 1981Date of Patent: August 19, 1986Assignee: L'Air LiquideInventor: Pierre Thirion
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Patent number: 4581128Abstract: A sour liquid hydrocarbon feedstock is desulfurized upon contact with a hydrogen gas in the presence of a catalyst to obtain a low sulfur product and a hydrogen sulfide gas by-product. The hydrogen sulfide gas is treated with an anthraquinone which is dissolved in a solvent having a polarity which is greater than 3 Debye units, to produce sulfur and oxygen. The oxygen is used to oxidize a hydrocarbon fuel and produce the hydrogen gas used in the initial desulfurization step.Type: GrantFiled: January 14, 1985Date of Patent: April 8, 1986Assignee: Marathon Oil CompanyInventors: Mark A. Plummer, Carle C. Zimmerman, Jr.
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Patent number: 4552748Abstract: A method in the production of hydrogen peroxide is described, utilizing the so-called anthraquinone process in which alkylated anthraquinones dissolved in organic solvents to form a liquid working solution, are alternately reduced and oxidized. The working solution is subjected to catalytic hydrogenation by contacting it with hydrogen in the presence of a hydrogenation catalyst. The contact with hydrogen is established in a fixed catalyst bed comprising one or more solid catalyst bodies, each of which consists of a thin-walled, coherent, solid body of a structure forming parallel channels through which the working solution and hydrogen gas are allowed to pass. The channels of the catalyst bed are of equal length and parallel to the direction of flow of the working solution. The catalyst preferably is provided in a thin layer on the walls of the structure, preferably by means of a porous carrier.Type: GrantFiled: September 6, 1983Date of Patent: November 12, 1985Assignee: EKA ABInventors: Carl T. Berglin, Wolfgang Herrmann
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Patent number: 4544543Abstract: The invention is for a process for removing unalkylated anthraquinones from alkylated anthraquinone by forming a solution thereof, reducing the solution sufficiently so that at least part of the unalkylated anthraquinone is in the reduced form, and extracting the reduced solution in the absence of an oxidizing agent with an aqueous alkaline solution. The process is especially suited for removing anthraquinone from an alkylated anthraquinone for use in the manufacture of hydrogen peroxide by reducing and oxidizing a solution of the alkylated anthraquinone.Type: GrantFiled: April 25, 1983Date of Patent: October 1, 1985Assignee: FMC CorporationInventors: Nathan D. Lee, Dalbir S. Sethi
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Patent number: 4541997Abstract: A process of reducing the oxygen content in gas mixtures to 0.0-1.5% by volume, in which process the gas is contacted with a solution containing anthrahydroquinone derivatives capable of being oxidized with molecular oxygen under formation of hydrogen peroxide. The supply of oxygen is so adjusted that the amount of oxygen supplied, upon quantitative formation of hydrogen peroxide, stoichiometrically corresponds to not more than 90%, preferably 50%, of the supplied amount of anthrahydroquinone derivative. The hydrogen peroxide content at the contact surfaces between the solution and the gas must not exceed 100 millimols per liter at a simultaneous oxygen gas pressure of not more than 100 millibars. The oxygen-poor gas mixture in accordance with the process of this invention may be used as a protective or inert gas in chemical process industries where use is made of inflammable gases.Type: GrantFiled: February 16, 1983Date of Patent: September 17, 1985Assignee: EKA ABInventor: Gustaf F. Bengt
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Patent number: 4539196Abstract: The invention provides a process to increase the mol ratio of nuclearly hydrogenated working compound to the total working solution for the production of hydrogen peroxide by the cyclic reduction, oxidation, and extraction of an alkylated anthraquinone. The process produces the nuclearly hydrogenated working compound without producing substantial quantities of undesired by-products.Type: GrantFiled: April 19, 1984Date of Patent: September 3, 1985Assignee: FMC CorporationInventors: Dalbir S. Sethi, Morton Meadow, Elizabeth A. Scarito nee Bagnall
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Patent number: 4521531Abstract: A palladium-on-silica catalyst for the anthraquinone-hydroquinone method of preparing hydrogen peroxide is prepared by adding acid solutions of a palladium compound and of an additive metal salt to an aqueous slurry of silica particles, lowering the pH of the slurry to about 0.8-1.0, then incrementally raising the pH of the slurry to 2.3-2.7, to 3.8-4.2, then to 6.8-7.2, and then reducing the palladium compound to palladium metal.Type: GrantFiled: August 15, 1983Date of Patent: June 4, 1985Assignee: E. I. Du Pont de Nemours and CompanyInventor: John S. Coates
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Patent number: 4514376Abstract: The invention provides a process to increase the mol ratio of nuclearly hydrogenated working compound to the total working compound in a make-up solution to be added to the working solution of an operating plant in producing hydrogen peroxide by the cyclic reduction, oxidation, and extraction of an alkylated anthraquinone. The process produces the nuclearly hydrogenated working compound in the make-up solution without producing substantial quantities of undesired by-products.Type: GrantFiled: April 19, 1984Date of Patent: April 30, 1985Assignee: FMC CorporationInventor: Dalbir S. Sethi
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Patent number: 4508696Abstract: Improved recycle processes for preparing hydrogen peroxide to hydrogenating alkylanthraquinone in a solvent to form hydrogenated alkylanthraquinone, treating the resulting liquid with an oxygen-containing gas to form hydrogen peroxide and regenerate the quinone, extracting the hydrogen peroxide with water, and recycling the quinone, wherein the quinones are 2-ethylanthraquinone (EAQ) and 2-ethyl-5,6,7,8-tetrahydroanthraquinone (H.sub.4 EAQ) and losses of quinone are made up exclusively with H.sub.4 EAQ, the solvent being methylcyclohexyl acetate and a nine carbon-atom alkylbenzene, these processes providing reduced losses of the active intermediate and improved operation of the hydrogen peroxide production unit.Type: GrantFiled: September 21, 1984Date of Patent: April 2, 1985Assignee: Produits Chimiques Ugine KuhlmannInventor: Michel Coingt
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Patent number: 4503028Abstract: A method in the production of hydrogen peroxide by the anthraquinone process is described, in which method anthraquinone derivatives dissolved in a working solution are subjected alternatingly to hydrogenation and oxidation. To reduce the relative moisture in the working solution to a suitable level of 20-98%, preferably 40-85%, the working solution is dried prior to hydrogenation by contacting it with a gas or a gaseous mixture, the water vapor pressure of which is below that of the working solution. Suitable gases or gas mixtures are air or exhaust gases from the oxidation stage of the anthraquinone process.Type: GrantFiled: September 29, 1982Date of Patent: March 5, 1985Assignee: Eka ABInventors: Bengt G. Franz/e/ n, Wolfgang Herrmann
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Patent number: 4485084Abstract: The invention provides a process to manufacture hydrogen peroxide by cyclically reducing, oxidizing, and extracting a working compound dissolved in an inert solvent, with solvent and/or energy from the effluent from the oxidation step being recovered thereby increasing the economically feasible temperature and pressure ranges of the oxidation step.Type: GrantFiled: February 24, 1984Date of Patent: November 27, 1984Assignee: FMC CorporationInventor: William A. McIntyre
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Patent number: 4428922Abstract: In the anthraquinone process for manufacturing hydrogen peroxide an improvement is obtained in the productivity of a fixed-bed catalytic hydrogenator operating in the dispersed-bubble flow regime by premixing the hydrogen gas and the working solution by means of a static mixer.Type: GrantFiled: May 14, 1982Date of Patent: January 31, 1984Assignee: FMC CorporationInventor: Quentin G. Hopkins
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Patent number: 4428923Abstract: There is provided a continuous parallel current flow process for carrying out the catalytic hydrogenation with hydrogen or a hydrogen containing gas for the production of hydrogen peroxide in the anthraquinone process using palladium black suspended in the working solution at a temperature up to 100.degree. C. and a pressure up to 15 bar absolute in a reaction space constructed as a meandering tube system in which the hydrogenation is carried out in a loop reactor made of tubes of the same nominal diameter and arranged either vertically or horizontally and connected by curving tubes (tube elbows) at flow velocities in the tubes of more than 3 m/sec.Type: GrantFiled: November 9, 1982Date of Patent: January 31, 1984Assignee: Degussa AktiengesellschaftInventors: Wolfgang Kunkel, Jorg Kemnade, Dietrich Schneider
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Patent number: 4394369Abstract: An anthraquinone autoxidation process has been developed for producing hydrogen peroxide employing N-substituted-2-pyrrolidones as solvents for the anthrahydroquinone formed in the reduction step. These new solvents have improved solubility characteristics over prior solvents. Particular N-substitutents are alkyl and alkaryl groups containing 6 to 12 carbon atoms.Type: GrantFiled: May 24, 1982Date of Patent: July 19, 1983Assignee: FMC CorporationInventor: Wayne Ranbom
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Patent number: 4374820Abstract: An alkylanthraquinone working solution as used in the manufacture of hydrogen peroxide, in the oxidized form is cooled to from 20.degree. to 40.degree. C. and fed to a slurry type catalytic hydrogenator maintained at from 38.degree. to 60.degree. C., and 10 to 100 psig. From 10 to 90% of the catalyst free hydrogenated working solution is cooled to from 20.degree. to 40.degree. C. and recycled to the hydrogenator.Type: GrantFiled: July 29, 1981Date of Patent: February 22, 1983Assignee: E. I. Du Pont de Nemours and CompanyInventor: Thomas E. Guenter
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Patent number: 4351820Abstract: A process is disclosed for the regeneration, by thermal treatment, of used catalysts for a cyclical process for the production of hydrogen peroxide. According to the process, used aluminosilicate type catalyst is subjected to progressive heating up to a temperature between 700.degree. and 850.degree. C., in the presence of an oxidizing atmosphere circulating co-current to the catalyst being regenerated. The process can be carried out in a rotary furnace inclined to the horizontal by 0.7 to 1% and having radial fins on the lower section of its inner wall, and an adjustable diaphragm at its outlet.Type: GrantFiled: August 11, 1980Date of Patent: September 28, 1982Assignee: OxysyntheseInventor: Pierre Thirion
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Patent number: 4349526Abstract: Tetra substituted ureas wherein at least one substituent is an aryl group have proven very oxidation resistant in the anthraquinone process for making hydrogen peroxide. The urea nitrogen is directly attached to the aryl group. These ureas can be used as a single solvent or as a component of a mixture of solvents.Type: GrantFiled: July 14, 1981Date of Patent: September 14, 1982Assignee: Degussa AktiengesellschaftInventors: Gustaaf Goor, Wolfgang Kunkel
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Patent number: 4336241Abstract: Hydrogen peroxide production by oxidation of a 2-alkyl-9,10-dihydroxyanthracene, especially the 2-(t-butyl) compound, and catalytic hydrogenation of the resulting 2-alkylanthraquinone back to the dihydroxy compound, using a water-insoluble (bipyridyl) rhodium complex as hydrogenation catalyst. Especially such process carried continuously in a cell in which an organic phase is separated by a porous membrane from an aqueous phase, and the anthraquinone is hydrogenated on the organic side of the cell and hydrogen peroxide is obtained from the aqueous phase. Preferably the rhodium complex is formed with a bipyridyl ligand attached to polystyrene beads, whereby to assure that rhodium is not carried into the hydrogen peroxide production side of the cell.Type: GrantFiled: March 18, 1981Date of Patent: June 22, 1982Assignee: Allied CorporationInventors: Steven E. Diamond, Benjamin S. Tovrog, Frank Mares, Reginald T. Tang
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Patent number: 4258025Abstract: An amorphous silica supported palladium catalyst is provided which also contains a small amount of an additive metal compound selected from an oxide, hydroxide and carbonate of zirconium, thorium, hafnium, cerium, titanium and aluminum. By use of particular preparation conditions and the amount of additive metal salt raw material used, the additive metal compound deposits from solution before or simultaneously with a palladium compound. The additive metal compound deposits on the silica support and serves as a base for the subsequently deposited palladium compound which is later reduced to palladium metal. The described catalyst is particularly suitable as a hydrogenation catalyst in a cyclic process for the manufacture of hydrogen peroxide.Type: GrantFiled: November 2, 1979Date of Patent: March 24, 1981Assignee: E. I. Du Pont de Nemours and CompanyInventor: Harry B. Copelin
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Patent number: 4087458Abstract: This invention relates to an improvement in the process for preparation of 2-(amylbenzoyl)benzoic acid containing a high percentage of 2-(t-amylbenzoyl)benzoic acid. More particularly it relates to a process for preparation of 2-(amylbenozyl)benzoic acid wherein said 2-(amylbenzoyl)benzoic acid is prepared by reacting t-amylbenzene with phthalic anhydride in the presence of Lewis acid, characterized by that 2-(amylbenzoyl)benzoic acid containing a high percentage of 2-(t-amylbenzoyl)benzoic acid is produced by suppressing the undesirable isomerization reaction of the amyl radical by applying one of the means selected from the group consisting of the means of introducing an inert gas into the reaction system and the means of reducing the pressure of the reaction system. 2-(Amylbenzoyl)benzoic acid is a compound useful as the starting material of preparation of 2-amylanthraquinone which is an effective organic catalyst in the manufacture of hydrogen peroxide.Type: GrantFiled: May 6, 1977Date of Patent: May 2, 1978Assignee: Yamamoto Kagaku Gosei Co., Ltd.Inventors: Fumitoshi Emori, Yasuhisa Iwasaki, Takao Yoshimura
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Patent number: 4061598Abstract: A palladium-on-alumina catalyst having high activity and long life and which gives low anthraquinone usage in the cyclic anthraquinone process for making H.sub.2 O.sub.2 is produced by impregnating the alumina under conditions such that the pore surfaces are rendered alkaline and the rate of diffusion of catalytic metal into the pores is controlled.Type: GrantFiled: June 25, 1976Date of Patent: December 6, 1977Assignee: E. I. Du Pont de Nemours and CompanyInventor: Kamel Michel Makar
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Patent number: 4059619Abstract: Process for continuous production of substantially anhydrous solutions of perpropionic acid in benzene. Aqueous hydrogen peroxide is first reacted with propionic acid in the presence of acid catalyst to form perpropionic acid and water (1). The perpropionic acid is extracted with benzene (5), to provide a benzene phase containing the perpropionic acid (11) and an aqueous raffinate (7). The benzene phase is subjected to an extraction with water (12) involving at least 3 stages, to remove hydrogen peroxide, and the resulting benzene extract (15) is subjected to azeotropic distillation (26) to provide the anhydrous solution (17). The aqueous raffinate, which contains hydrogen peroxide, is distilled to remove water (8) and the resulting concentrate is recycled (2) for use in the reaction (1).Type: GrantFiled: April 28, 1976Date of Patent: November 22, 1977Assignees: Deutsche Gold-und Silber-Scheideanstalt Vormals Roessler, Bayer AktiengesellschaftInventors: Gunter Prescher, Gerd Schreyer, Otto Weiberg, Rolf Wirthwein, Helmut Waldmann, Hermann Seifert, Wulf Schwerdtel, Wolfgang Swodenk
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Patent number: 4046868Abstract: An improved process for the production of hydrogen peroxide is provided in which an (N,N-dialkyl) carboxylic acid amide having a solubility in water of less than 1 percent at 25.degree. C. is used as a solvent in the anthraquinone process.Type: GrantFiled: September 26, 1973Date of Patent: September 6, 1977Assignee: E. I. Du Pont de Nemours and CompanyInventor: Lawrence G. Vaughan
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Patent number: 3998937Abstract: 1-Alkyl and 1,3-dialkyl substituted-1,2,3,4-tetrahydroanthraquinones are provided which may also be alkyl substituted in the 6- and/or 7- position. These compounds are provided by condensing a naphthoquinone with an alkyl-substituted butadiene dimer, catalytically hydrogenating the adduct, then oxidizing the resulting hexahydro compound to the desired tetrahydroanthraquinone. Alternatively, the condensation product may be oxidized with a cupric compound or with air plus a weak base, and this compound catalytically hydrogenated and then oxidized to the corresponding tetrahydroanthraquinone. The compounds of this invention exhibit superior solubility in solvents commonly used in the cyclic process for manufacturing H.sub.2 O.sub.2 and thus enhance H.sub.2 O.sub.2 production.Type: GrantFiled: April 30, 1976Date of Patent: December 21, 1976Assignee: E. I. Du Pont de Nemours and CompanyInventor: Lawrence G. Vaughan
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Patent number: 3998936Abstract: Catalytic activity of a platinum group metal catalyst used in catalyzing the hydrogenation of a working solution of an alkylanthraquinone in a water-immiscible solvent in the manufacture of hydrogen peroxide, said catalyst having become at least partially inactivated, is regenerated by a process comprising contacting the catalyst in the presence of the working solution and in the absence of hydrogen with an oxidizing agent selected from the group consisting of an oxygen-containing gas and hydrogen peroxide.When the process of the invention is made an integral part of the cyclic anthraquinone process for producing hydrogen peroxide, there results an improvement in the latter process whereby the activity of the catalyst can be maintained at a high level.Type: GrantFiled: April 23, 1975Date of Patent: December 21, 1976Assignee: E. I. Du Pont de Nemours and CompanyInventors: Richard Edward Ernst, Bijan Amini, William John Bareford
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Patent number: 3965251Abstract: A working solution comprising anthraquinone and its derivatives, used for the production of hydrogen peroxide on becoming degraded by formation of non-effective anthraquinone is generated by an auto-oxidation process employing anthraquinone, which comprises:Contacting, at a temperature of below 130.degree.C., and in the presence of a catalyst comprising a metal selected from a platinum group and supported on a carrier, said degraded working solution, which comprises non-effective anthraquinone and tetrahydroanthraquinone with an olefinic compound whose hydrogenation product is gaseous at said contact temperature andSubsequently, contacting the thus treated working solution, at a temperature above 130.degree.C., and in the presence of a catalyst comprising a metal selected from the platinum group and supported on a carrier, with an olefinic compound whose hydrogenation product is gaseous at said contact temperature,Said method being characterized by the fact that at a temperature below 130.degree.C.Type: GrantFiled: August 2, 1973Date of Patent: June 22, 1976Assignee: Mitsubishi Gas Chemical Company, Inc.Inventors: Hiroshi Shin, Junichiro Sugano, Tadashi Yoshii, Kichiro Iwamoto, Yasuhisa Kuriyama, Minoru Kakuda
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Patent number: 3962288Abstract: 1-Alkyl and 1,3-dialkyl substituted-1,2,3,4-tetrahydroanthraquinone are provided which may also be alkyl substituted in the 6- and/or 7- position. These compounds are provided by condensing a naphthoquinone with an alkyl-substituted butadiene dimer, catalytically hydrogenating the adduct, then oxidizing the resulting hexahydro compound to the desired tetrahydroanthraquinone. Alternatively, the condensation product may be oxidized with a cupric compound or with air plus a weak base, and this compound catalytically hydrogenated and then oxidized to the corresponding tetrahydroanthraquinone. The compounds of this invention exhibit superior solubility in solvents commonly used in the cyclic process for manufacturing H.sub.2 O.sub. 2 and thus enhance H.sub. 2 O.sub.2 production.Type: GrantFiled: March 14, 1974Date of Patent: June 8, 1976Assignee: E. I. Du Pont de Nemours and CompanyInventor: Lawrence G. Vaughan
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Patent number: 3952089Abstract: Hydrogen peroxide solution is produced by the anthraquinone process as a crude extraction product of over 50% H.sub.2 O.sub.2, using working solutions having (1) as the reaction carrier quinone derivatives having a molecular weight below 275, (2) H.sub.2 O.sub.2 capacities below 15 grams H.sub.2 O.sub.2 /liter of working solution, and (3) distribution coefficients of over 30, preferably over 40. The crude H.sub.2 O.sub.2 extract is water stripped to above 80% concentration and then concentrated to above 90% by freezing.Type: GrantFiled: May 1, 1972Date of Patent: April 20, 1976Assignee: Deutsche Gold- und Silber-Scheideanstalt vormals RoesslerInventors: Gerhard Kabisch, Rudolf Trube
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Patent number: 3949063Abstract: A process for regenerating working solutions used in cyclic processes for the manufacture of hydrogen peroxide using anthraquinones, the process consisting of a first distillation stage in which the solvent is separated under a pressure not greater than atmospheric pressure, and a second distillation stage in which the quinones and "light degraded products" are separated under a lower pressure. All the distillation products are used as a new working solution, the vapors of the second distillation stage being condensed on a liquid film of constantly renewed cold solvent originating from condensable vapors of the first distillation stage.Type: GrantFiled: November 6, 1974Date of Patent: April 6, 1976Assignee: OxysyntheseInventors: Michel Coingt, Pierre Thirion