Abstract: The invention concerns a method for making an aqueous solution of hydrogen peroxide. More particularly, it concerns a method for making hydrogen peroxide directly from hydrogen and oxygen, finely dispersed in an aqueous acid medium comprising a catalyst and at least a surfactant. The invention also concerns a device for implementing said method.
Abstract: Aqueous-organic or organic hydrogen peroxide solutions can be produced by direct synthesis in the presence of a catalyst fixed bed and an organic solvent. According to the invention, a non-explosive gas mixture comprising H2 and O2 is employed and a liquid reaction medium comprising organic solvent and bromide and/or iodide is passed over the fixed bed with a cross-section loading of at least 0.3 m/h. In the case of a trickle bed procedure with a cross-section loading of 0.3 m/h to 2 m/h, 4 to 10 wt. % methanolic H2O2 solutions can be prepared with a high productivity.
Type:
Application
Filed:
September 25, 2002
Publication date:
May 1, 2003
Inventors:
Thomas Haas, Guido Stochniol, Jurgen Rollmann
Abstract: Process for the on-site purification of an aqueous hydrogen peroxide solution, in which the solution is made to pass through a resin bed capable, at least partially, of adsorbing or absorbing the impurities present in the solution. The hydrogen peroxide solution is injected into the resin bed and passes through the latter at an approximately linear velocity preferably of between 10 m/h and 50 m/h and more preferably between 10 m/h and 20 m/h, while the resin bed is kept substantially compacted for at least 50% of the time during which the solution is being purified by coming into contact with the said resin.
Type:
Grant
Filed:
October 18, 2000
Date of Patent:
April 1, 2003
Assignee:
L'Air Liquide Societe Anonyme a Directoire et Conseil de
Surveillance pour l'Etude et l'Exploitation des Procedes Georges
Claude
Abstract: A method of integrated resin preconditioning and hydrogen peroxide purification is provided. The method includes preconditioning a resin by washing the resin with deionized water to produce a washed resin, and contacting an effective amount of a preconditioning hydrogen peroxide solution with the washed resin to remove impurities from the washed resin, thereby producing a preconditioned resin.
Type:
Grant
Filed:
April 4, 2001
Date of Patent:
March 25, 2003
Assignee:
Air Liquide America Corporation
Inventors:
Mary Dykstra Havlicek, Joe G. Hoffman, Wallace Yuan
Abstract: The invention discloses a dual-functional catalyst composition and an integrated process for production of olefin epoxides including propylene oxide by catalytic reaction of hydrogen peroxide from hydrogen and oxygen with olefin feeds such as propylene. The epoxides and hydrogen peroxide are preferably produced simultaneously in situ. The dual-functional catalyst comprises noble metal crystallites with dimensions on the nanometer scale (on the order of <1 nm to 10 nm), specially dispersed on titanium silicalite substrate particles. The dual functional catalyst catalyzes both the direct reaction of hydrogen and oxygen to generate hydrogen peroxide intermediate on the noble metal catalyst surface and the reaction of the hydrogen peroxide intermediate with the propylene feed to generate propylene oxide product.
Abstract: A novel compound which can be used in the field of separation and purification of gases is disclosed. The compound can be incorporated into a silica gel incorporating polyazacycloalkane structural units for separating a predetermined gas from a mixture of gases. The mixture of gases is brought into contact with a metallated hybrid gel under conditions which make possible the absorption of the gas to be separated, followed by a phase of desorption of the attached gas, and the recovery of the gas.
Type:
Grant
Filed:
July 25, 2000
Date of Patent:
February 25, 2003
Assignee:
L′Air Liquide, Societe Anonyme a Directoire et Conseil
de Surveillance pour l′Etude et l′Exploitation des
Procedes Georges Claude
Inventors:
Robert Corriu, Catherine Reye, Ahmad Mehdi, Gérard Dubois, Claude Chuit, Franck Denat, Bruno Roux-Fouillet, Roger Guilard, Gilles Lagrange, Stéphane Brandes
Abstract: Provided is a method of preconditioning a resin useful for removal of organic impurities from a hydrogen peroxide solution. The method involves the steps of (a) rinsing the resin with deionized water; (b) contacting the resin with an acid solution; and (c) rinsing the acid treated resin with deionized water. Also provided is a resin preconditioned in accordance with the method, and a method of removing organic impurities from a hydrogen peroxide solution using the preconditioned resin. The invention has particular applicability to the removal of total organic carbon (TOC) impurities from a hydrogen peroxide solution which can be used in the manufacture of semiconductor devices.
Type:
Application
Filed:
April 4, 2001
Publication date:
January 30, 2003
Inventors:
Mary Dykstra Havlicek, Joe G. Hoffman, Wallace Yuan
Abstract: In a process for preparing an aqueous and/or alcoholic solution of hydrogen peroxide by reaction of hydrogen and oxygen in a trickle-bed reactor over a supported catalyst comprising a noble metal, the apparent flow direction of the gas stream and the apparent flow direction of the liquid stream are not parallel to one another. The apparent flow direction of the gas stream preferably runs radially from the longitudinal axis to the circumference of the reactor. The process allows high gas throughputs with a small pressure drop.
Type:
Application
Filed:
July 15, 2002
Publication date:
January 23, 2003
Applicant:
BASF Aktiengesellschaft
Inventors:
Martin Fischer, Thomas Butz, Klemens Massonne
Abstract: Provided are a preconditioned resin and methods of preparation thereof as well as methods for purifying hydrogen peroxide solutions. The method includes preconditioning an anion exchange resin, wherein an anion exchange resin bed is provided and carbon dioxide gas is passed through the resin bed.
Type:
Application
Filed:
April 4, 2001
Publication date:
January 23, 2003
Inventors:
Mary D. Havlicek, David L. Snyder, Joe G. Hoffman, Marshall E. Cummings
Abstract: A method of integrated resin preconditioning and hydrogen peroxide purification is provided. The method includes preconditioning a resin by washing the resin with deionized water to produce a washed resin, and contacting an effective amount of a preconditioning hydrogen peroxide solution with the washed resin to remove impurities from the washed resin, thereby producing a preconditioned resin.
Type:
Application
Filed:
April 4, 2001
Publication date:
January 23, 2003
Inventors:
Mary Dykstra Havlicek, Joe G. Hoffman, Wallace Yuan
Abstract: The present invention is a method of stabilizing hydrogen peroxide in an aqueous solution, such as a circulating water slurry, comprising a peroxide, such as hydrogen peroxide. The aqueous solution may include organic matter. The method comprises adding an aldehyde donor, such as a methylolhydantoin, to the solution (or slurry). The inventors have discovered that aldehyde donors significantly reduce the decomposition of hydrogen peroxide by catalase and other peroxide decomposing enzymes, which are often present in recycled paper. As a result, less hydrogen peroxide needs to be added to a solution to effectively bleach organic matter in the solution. Furthermore, aldehyde donors are safe to handle and cost effective. Another embodiment is a method of bleaching recycled papers in a circulating water slurry comprising organic matter. The method comprises adding hydrogen peroxide and an aldehyde donor to the slurry.
Type:
Application
Filed:
April 12, 2002
Publication date:
December 5, 2002
Applicant:
Lonza, Inc.
Inventors:
Bill Ney, Richard Sinden, Philip Gerdon Sweeny, Patrick Jay Lutz, Olga Borokhov
Abstract: A supported gold-containing catalyst is effective for producing hydrogen peroxide from the direct liquid-phase reaction of hydrogen and oxygen.
Abstract: A catalytic process and a device for preparing, in absolute safely, aqueous hydrogen peroxide solutions at high concentration levels directly from hydrogen and oxygen; more particularly, a method whereby hydrogen and oxygen are injected, into the aqueous medium in proportions corresponding to the flammability range of the hydrogen-oxygen mixture, and are present in proportions outside the flammability range in the continuous gas phase. The invention also concerns a device for implementing the method.
Abstract: A supported gold-containing catalyst is effective for producing hydrogen peroxide from the direct liquid-phase reaction of hydrogen and oxygen.
Abstract: A method for regenerating used supported noble metal catalysts, which method includes solvent cleaning the used catalyst by contact with a suitable organic liquid cleaning solvent such as alcohols, ketones and such to remove organic deposits from the catalyst, followed by drying and calcining at elevated temperature to remove any remaining organic deposits from the catalyst, then treating the catalyst with an organo-metallic complex forming agent having ionization constant pK1 greater than about 2.5, such as glycolic acid and the like. The organic-metallic complex forming agent acts to break down large clusters of noble metal particles such as palladium (Pd) and redistributes the metal particles on the catalyst support such as alumina (Al2O3) in the same or other larger pores, so as to increase catalyst surface area and catalytic activity to provide a catalytic activity level at least 80% or even exceeding that of the fresh catalyst.
Abstract: The above objects are achieved by providing a novel process for the production of hydrogen peroxide, by the non-hazardous direct oxidation of hydrogen by oxygen to hydrogen peroxide, without the formation of an explosive H2 and O2 gas mixture, using a novel tubular hydrophobic composite Pd-membrane catalyst, represented by a formula:
HPM (c)/SOMF (b)/MxPd1−x(a)/IPM
Wherein: IPM is an inorganic porous membrane, permeable to all gases and vapors, in a form of tube having a thickness of at least 0.5 mm and internal diameter of at least 0.6 cm; Mx Pd1−x is a metal alloy, permeable only to hydrogen gas, deposited on the inner side of IPM; Pd is a palladium metal; M is a metal selected from copper, silver, gold, noble metals other than palladium, or a mixture of two or more thereof; x is a mole fraction of the metal M in the metal alloy (MxPd1−x) in the range from about 0.03 to about 0.6; (a) is a weight of the metal alloy per unit area of IPM in the range from about 5.0 g.
Type:
Grant
Filed:
September 5, 2000
Date of Patent:
August 13, 2002
Assignee:
Council of Scientific & Industrial Research
Abstract: A process for catalytically directly producing hydrogen peroxide (H2O2) product from hydrogen and oxygen-containing feeds by contacting them with a supported noble metal phase-controlled catalyst and a suitable organic liquid solvent having a Solvent Selection Parameter (SSP) between 0.14×10−4 and 5.0×10−4 at reaction condition of 0-100° C. temperature and 100-3,000 psig pressure. Unconverted feed gas and organic liquid solvent solution are usually recovered and recycled back to the reactor along with any recovered catalyst. If desired, the hydrogen peroxide product can be fed together with an organic chemical feedstock such as propylene and with the organic liquid solvent solution into a second catalytic reaction step which oxidizes the feedstock to produce a desired crude oxidized organic product such as propylene oxide, which may be purified by distillation steps and recovered from the solvent solution.
Type:
Application
Filed:
May 29, 2001
Publication date:
August 8, 2002
Inventors:
Bing Zhou, Michael A. Rueter, Lap-Keung Lee, Bruce P. Pelrine
Abstract: A process for the continuous preparation of very highly concentrated hydrogen peroxide having a content of greater than 80 wt.%, especially over 98 wt.%, by suspension crystallization and after-treatment of the H2O2 crystals. The after-treatment takes the form of countercurrent washing in a hydraulic or mechanical washing column with a packed crystal bed. Hydrogen peroxide is disclosed having a concentration of from 99.9 to 100 wt.% and a content of TOC, nitrate, phosphate, nickel and tin of in each case less than 4 mg/l.
Type:
Application
Filed:
November 30, 2001
Publication date:
June 6, 2002
Inventors:
Stefan Nordhoff, Matthias Creutz, Stefan Gross, Rudolf Wagner
Abstract: A process for the concentration of aqueous hydrogen peroxide by discontinuous crystallization. A cooling surface is arranged in a crystallizing vessel and first wetted with hydrogen peroxide and then cooled at a high cooling rate, whereupon seed crystals form. The cooling rate is at least 1 K/s, preferably from 10 to 30 K/s. When the vessel has been filled with H2O2 starting material, the latter crystallizes, starting from the seed crystals, and forms a crystal layer. When the mother liquor of lower H2O2 concentration has been discharged, there follows a sweating operation with a slow increase in temperature, as a result of which the H2O2 concentration in the crystal layer is increased further.
Type:
Application
Filed:
October 26, 2001
Publication date:
May 30, 2002
Inventors:
Matthias Creutz, Stefan Nordhoff, Rudolf Wagner, Jurgen Glenneberg, Dieter Moller
Abstract: A process for the direct synthesis of hydrogen peroxide from hydrogen and oxygen is carried out in the presence of a noble metal catalyst. The selectivity for H2 and/or the maximum H2O2 concentration can be increased by using a catalyst of palladium or at least two metals selected from Group VIII and Group I of the Periodic Table of Elements, which catalyst has been produced by spray pyrolysis or flame pyrolysis.
Type:
Grant
Filed:
March 20, 2000
Date of Patent:
May 14, 2002
Assignee:
Degussa-Huls AG
Inventors:
Birgit Bertsch-Frank, Ina Hemme, Lukas Von Hoppel, Stipan Katusic, Jürgen Rollmann
Abstract: A process for preparing a hydrogen peroxide solution having a hydrogen peroxide content of not less than 2.5% by weight, which comprises continuously reacting hydrogen and oxygen in an aqueous, alcoholic or aqueous/alcoholic reaction medium in the presence of a catalyst containing palladium.
Type:
Grant
Filed:
April 15, 1999
Date of Patent:
April 23, 2002
Assignee:
BASF Aktiengesellschaft
Inventors:
Martin Fischer, Gerd Kaibel, Achim Stammer, Klemens Flick, Stefan Quaiser, Wolfgang Harder, Klemens Massonne
Abstract: A cyclic anthraquinone process for producing hydrogen peroxide using at least two differently substituted 2-alkylanthraquinones and/or their tetrahydro derivatives. The working solution to be used contains (i) at least one reaction carrier from the series 2-(4-methyl-3-pentenyl) anthraquinone (IHEAQ), 2-(4-methylpentyl) anthraquinone (IHAQ) and their di- and tetrahydro derivatives such as, in particular 2-(4-methylpentyl)-&bgr;-tetrahydroanthraquinone (THIHAQ), and (ii) at least one reaction carrier from the series of the 2-(C1- to C5)-alkylanthraquinones, especially 2-ethylanthraquinone (EAQ), and their tetrahydro derivatives. The reaction carriers according to (i) make up 5 to 95 molar %, especially 20 to 50 molar % of all reaction carrier. The method is distinguished by greater H2O2 capacity, improved hydrogenation kinetics and lesser susceptibility to disturbances. A method for making THIHAQ is also disclosed.
Type:
Grant
Filed:
July 27, 2000
Date of Patent:
March 12, 2002
Assignee:
Degussa AG
Inventors:
Jürgen Glenneberg, Gustaf Goor, Eugen Staab, Hubert Angert
Abstract: A description follows of a bimetallic catalyst, obtained by dispersing in sequence and alternating the precursors of the single metal components of the catalyst on a carrier, and a process for the synthesis of hydrogen peroxide by the direct reaction of hydrogen with oxygen, in a solvent medium containing a halogenated promoter and an acid promoter, in the presence of said catalyst.
Type:
Application
Filed:
June 1, 2001
Publication date:
March 7, 2002
Applicant:
ENI S.p.A.
Inventors:
Giuseppe Paparatto, Rino D' Aloisio, Giordano De Alberti, Roberto Buzzoni
Abstract: A process-is described for the continuous production of alcoholic or hydro-alcoholic solutions of hydrogen peroxide in a concentration ranging from 2 to 10% by weight and their direct use in oxidation processes.
Type:
Application
Filed:
June 1, 2001
Publication date:
February 28, 2002
Applicant:
ENI S.p.A
Inventors:
Giuseppe Paparatto, Franco Rivetti, Pietro Andrigo, Giordano De Alberti
Abstract: The present invention relates to a novel hydrophobic multicomponent catalyst useful in the direct oxidation of hydrogen to hydrogen peroxide and to a method for the preparation of such catalyst. More specifically, this invention relates to a novel hydrophobic muticomponent catalyst comprising a hydrophobic polymer membrane deposited on a Pd containing acidic catalyst, useful for the direct oxidation of hydrogen by oxygen to hydrogen peroxide, an a method for preparing the same.
Type:
Grant
Filed:
January 19, 2000
Date of Patent:
February 12, 2002
Assignee:
Council of Scientific and Industrial Research
Abstract: A process for producing a purified aqueous hydrogen peroxide solution, comprising passing a charged aqueous hydrogen peroxide solution containing impurities through a purifier tower packed with an ion exchange resin, a chelate resin or an adsorption resin to thereby purify the charged aqueous hydrogen peroxide solution, wherein there are provided a feed pump of given output capable of causing the charged aqueous hydrogen peroxide solution to flow to the purifier tower and further a flow sensor capable of sensing a flow rate of charged aqueous hydrogen peroxide solution being fed to the purifier tower and wherein the output of the feed pump is controlled in cooperation with the flow sensor so as to bring the charged aqueous hydrogen peroxide solution into contact with the ion exchange resin, chelate resin or adsorption resin while maintaining the flow of charged aqueous hydrogen peroxide solution at a constant rate.
Abstract: The present invention provides a process for producing a highly purified aqueous hydrogen peroxide solution from which silicon oxide impurities are removed to a minimum by purifying an aqueous hydrogen peroxide solution containing silicon oxide impurities.
Abstract: A method for synthesizing hydrogen peroxide comprises the steps of: synthesizing an analog of anthraquinone that is miscible or soluble in carbon dioxide; reacting the analog of anthraquinone with hydrogen in carbon dioxide to produce a corresponding analog of tetrahydroquinone; and reacting the analog of tetrahydroquinone with oxygen to produce the hydrogen peroxide and regenerate the analog of anthraquinone. A chemical compound having the formula:
wherein R1, R2, R3, R4, R5, R6, R7, and R8 are independently, the same or different, H, RC, or RSRC, wherein RS is a spacer group and RC is a fluoroalkyl group, a fluoroether group, a silicone group, an alkylene oxide group, a fluorinated acrylate group, or a phosphazine group, and wherein at least one of R1, R2, R3, R4, R5, R6, R7, and R8 is not H.
Abstract: Process for the industrial production of hyperpure hydrogen peroxide also having high titre up to 60-70% by weight characterized in that the hydrogen peroxide produced in an industrial plant is directly fed to a purification unit, being part of the same production plant, in which the inverted osmosis, separation of the the high purity permeate flow and direct recycle of the concentrated flow to the production plant, are carried out.
Abstract: The invention concerns a process of continuously producing hydrogen peroxide by direct reaction between hydrogen and oxygen in a gaseous reaction mixture in contact with a catalyst maintained in a reactor, wherein a gaseous reaction mixture containing hydrogen and oxygen is supplied to the reactor through an inlet and hydrogen peroxide enriched gas is withdrawn from the reactor through an outlet. According to the invention the temperature difference in the gaseous reaction mixture in contact with the catalyst between a position just after the inlet to the reactor and a position at the outlet of the reactor is maintained below about 40° C.
Type:
Grant
Filed:
December 22, 1998
Date of Patent:
October 9, 2001
Assignee:
Akzo Nobel N.V.
Inventors:
Mats Nyström, Johan Wanngård, Wolfgang Herrmann
Abstract: Process for purifying an aqueous hydrogen peroxide solution containing impurities, some of which are in ionic form, in which the said aqueous solution is purified by passing it through at least one first resin of anionic type in order to remove at least some anionic impurities, and then through a second resin of cationic type in order to remove at least some of the cationic impurities, or vice versa, characterized in that at least a first and a second bed of a first resin of anionic type are arranged in parallel, in that the aqueous solution is directed alternately onto the said first or the said second bed, and in that changeover from the first bed to the second bed (or vice versa) is carried out when the said first [lacuna] is at least partially saturated with at least one of the anions constituting the anionic impurities.
Type:
Grant
Filed:
October 15, 1999
Date of Patent:
October 2, 2001
Assignee:
L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation
des Procedes Georges Claude
Abstract: The invention is relative to a method of producing hydrogen peroxide by direct synthesis in which hydrogen and oxygen are reacted in the presence of a heterogeneous, carrier-free or carrier-bound catalyst containing at least one noble metal in the presence or absence of a solvent and to a catalyst for carrying out the method.
Type:
Application
Filed:
February 26, 2001
Publication date:
September 27, 2001
Inventors:
Birgit Bertsch-Frank, Ina Hemme, Jurgen Rollmann, Stipan Katusic, Torsten Balduf, Catrin D. Becker, Werner Wildner, Rudiger Schutte
Abstract: A method that employs a dilute solution, such as a dilute hydrogen peroxide solution, and concentrates the dilute solution to a yield a concentrated solution. A concentrated solution prepared by the method of the invention is useful as a rocket fuel, a laser fuel and industrial and laboratory chemical reagents.
Type:
Grant
Filed:
December 17, 1998
Date of Patent:
September 18, 2001
Assignee:
Iowa State University Research Foundation, Inc.
Abstract: The present invention relates to a catalyst consisting of a metal of the VIII group supported on acid activated carbon functionalized with sulfonic groups, a process for the synthesis of hydrogen peroxide from hydrogen and oxygen which uses said catalyst and the use of the hydrogen peroxide solution in oxidation processes catalyzed by titanium-silicalite.
Type:
Grant
Filed:
August 3, 1999
Date of Patent:
September 4, 2001
Assignee:
Enichem S.p.A.
Inventors:
Giuseppe Paparatto, Rino D'Aloisio, Giordano De Alberti, Piero Furlan, Vittorio Arca, Roberto Buzzoni, Laura Meda
Abstract: Process for the industrial production of hyperpure hydrogen peroxide also having high titer up to 60-70% by weight characterized in that the hydrogen peroxide produced in an industrial plant is directly fed to a purification unit, being part of the same production plant, in which the inverted osmosis, separation of the the high purity permeate flow and direct recycle of the concentrated flow to the production plant, are carried out.
Abstract: Ascorbic acid and/or ascorbic acid salt is made to act together with oxygen on an organic compound. Alternatively, light radiation is applied during chemical action with oxygen so as to improve a composition efficiency of an organic compound and obtain a preferable decomposition amount. This reduces the load caused by an organic compound decomposition on the environment.
Abstract: A process for preparing a hydrogen peroxide solution having a hydrogen peroxide content of not less than 2.5% by weight, which comprises continuously reacting hydrogen and oxygen in an aqueous, alcoholic or aqueous/alcoholic reaction medium in the presence of a catalyst containing palladium.
Type:
Application
Filed:
April 15, 1999
Publication date:
June 14, 2001
Inventors:
MARTIN FISCHER, GERD KAIBEL, ACHIM STAMMER, KLEMENS FLICK, STEFAN QUAISER, WOLFGANG HARDER, KLEMENS MASSONNE
Abstract: A basic hydrogen peroxide composition is described, wherein the basic hydrogen peroxide is formed by mixing aqueous potassium hydroxide and aqueous hydrogen peroxide in a mole ratio such that the resulting basic hydrogen peroxide composition does not crystallize when maintained at a temperature down to −21° C. The basic hydrogen peroxide composition is especially suitable for use with chemical oxygen iodine laser systems. The mole ratio of hydrogen peroxide to potassium hydroxide corresponds to a composition represented by at least one location within a triangular region on a triangular phase diagram which is substantially bounded by the shortest line having coordinates (26.4, 16.0, 57.6), (62.3, 37.7, 0.0), and (46.8, 53.2, 0.0), wherein these coordinates correspond to the respective weight percentages of potassium hydroxide, hydrogen peroxide and water.
Abstract: Process for manufacturing a purified aqueous hydrogen peroxide solution, in which a crude aqueous hydrogen peroxide solution is subjected to a washing operation with at least one organic solvent which has been subjected to a purification treatment prior to the washing operation.
Aqueous hydrogen peroxide solution with a TOC, defined according to ISO standard 8245, of less than or equal to 72 mg/l.
Abstract: The invention relates to a process for continuously producing hydrogen peroxide comprising the steps of feeding hydrogen and oxygen containing gas to a reactor provided with a catalyst; contacting the hydrogen and oxygen gas with the catalyst and thereby forming hydrogen peroxide, and; withdrawing hydrogen peroxide containing gas from the reactor; wherein the catalyst comprises a solid catalytically active material at least partially covered with a layer of a stationary phase different from the catalytically active material.
Type:
Grant
Filed:
December 22, 1998
Date of Patent:
April 3, 2001
Assignee:
Akzo Nobel N.V.
Inventors:
Mats Nyström, Johan Wanngård, Wolfgang Herrmann
Abstract: A particulate supported noble metal phase-controlled catalyst material having 5-1000 &mgr;m surface area of 50&mgr;500 m2/gm is provided for use in direct catalytic production of hydrogen peroxide (H2O2) product from hydrogen and oxygen-containing feedstreams. The catalyst is made by depositing phase controlled crystals of a noble metal such as palladium on a suitable particulate support material such as carbon black, by utilizing a precursor solution of the metal and a suitable control ionic polymer having molecular weight of 300-8000 such as sodium polyacrylate in a selected metal to polymer molar ratio of 1:0.1 to 1:10, which procedure provides desired phase control of the noble metal atoms to form widely dispersed minute noble metal crystals on the support material. The invention includes methods for making the catalyst, and also a process for utilizing the catalyst to directly produce high yields of hydrogen peroxide (H2O2) product from hydrogen and oxygen-containing gaseous feedstreams.
Abstract: A process for making an improved bulk catalyst having a Group VIII metal, such catalyst being useful in producing H.sub.2 O.sub.2 from H.sub.2 and O.sub.2 and/or in producing H.sub.2 from water. The method incorporates the Group VIII metal within the "pillars" of the porous catalyst, without leaving a significant amount of the Group VIII metal on or near the outside surface of the catalyst, by hydrothermal incorporation of the Group VIII metal into the porous pillars.
Type:
Grant
Filed:
March 19, 1999
Date of Patent:
November 7, 2000
Inventors:
Mark E. Thompson, Venkatesan V. Krishnan, Alexandre G. Dokoutchaev
Abstract: An aqueous solution of hydrogen peroxide is produced by direct synthesis from hydrogen and oxygen in the presence of a heterogeneous catalyst. According to the invention, a gas mixture comprising H.sub.2 and O.sub.2, essentially saturated or supersaturated with water (=containing fog) is fed into a reactor containing the catalyst. The volume ratio of the gas mixture fed in (standard liters per hour) to liquid removed (liters per hour) is adjusted to a value equal to or greater than 15,000, especially 20,000 to 50,000, and the gas mixture leaving the reactor is recycled after replenishment with H.sub.2, O.sub.2, and H.sub.2 O vapor. Solutions with high H.sub.2 O.sub.2 concentration can be obtained according to the invention without additional concentration.
Type:
Grant
Filed:
April 12, 1999
Date of Patent:
September 12, 2000
Assignee:
Degussa-Huls Aktiengesellschaft
Inventors:
Birgit Bertsch-Frank, Torsten Balduf, Catrin Becker-Balfanz, Ina Hemme, Jurgen Rollmann, Rudiger Schutte, Werner Wildner
Abstract: The present invention relates to a gauze catalyst based on titanium or vanadium zeolites and inert gauze fabrics which is suitable for accelerating oxidation reactions such as epoxidation of olefins, hydrogen peroxide production or hydroxylamine synthesis.
Type:
Grant
Filed:
August 26, 1998
Date of Patent:
August 22, 2000
Assignee:
BASF Aktiengesellschaft
Inventors:
Ulrich Muller, Franz Josef Brocker, Georg Heinrich Grosch, Hermann Putter, Michael Schulz, Norbert Rieber, Wolfgang Harder
Abstract: A method of purifying an aqueous solution of hydrogen peroxide by using an ion exchange resin and a adsorbent to obtain a highly pure aqueous solution of hydrogen peroxide with a metal concentration of not more than 0.1 ppb and a total organic carbon concentration of not more than 10 ppm, which comprises, in the order of purificatory passage of the solution, (A) a step of removing dissociable impurities by means of a mixed bed ion exchange resin, (B) a step of removing undissociable impurities by means of a hydrophilic porous adsorbent having a specific surface of not less than 1000 m.sup.2 /g, and (C) a step of removing dissociable impurities by means of a mixed bed ion exchange resin.
Abstract: The invention relates to a method and apparatus for safely producing hydrogen peroxide by injecting dispersed minute bubbles of hydrogen and oxygen into a rapidly flowing liquid medium. The minute bubbles are surrounded by the liquid medium of sufficient volume for preventing an explosive reaction between the hydrogen and oxygen. The liquid medium is formed of an acidic aqueous solution and a Group VIII metal catalyst. Hydrogen is sparged into the flowing medium for dissolution of the hydrogen in the medium. Oxygen bubbles are reacted with the dissolved hydrogen for producing hydrogen peroxide. Preferably, the liquid medium has a velocity of at least 10 feet per second for providing a bubbly flow regime in the reactor. The invention allows the direct combination of oxygen and hydrogen while preventing propagation of an explosive condition within the reactor. The method and apparatus provide for the safe production of hydrogen peroxide with low manufacturing costs.
Abstract: There is herein disclosed a method for preparing high-purity aqueous hydrogen peroxide by bringing aqueous hydrogen peroxide into contact with a strongly basic anion exchange resin, said method comprising the step of using the strongly basic anion exchange resin which is converted into a form of an exchange group at the time of the purification of aqueous hydrogen peroxide by bringing the strongly basic anion exchange resin into contact with a liquid agent passed through a filter having an average pore diameter of 1.0 .mu.m or less.According to the present invention, aqueous hydrogen peroxide containing inorganic impurities such as metals and metallic compounds can be purified to prepare extremely high-purity aqueous hydrogen peroxide.
Abstract: Provided is a process for the preparation of an ultrapure hydrogen peroxide solution to be purified through at least one bed of anion-exchange adsorbents and at least one bed of cation-exchange adsorbents. The at least one bed of anion-exchange adsorbents contains carboxylate ion of formula R--COO.sup.- in which R represents a hydrogen atom, an aryl radical containing from 6 to 10 carbon atoms or an alkyl radical containing from 1 to 4 carbon atoms. The aryl and alkyl radicals are either unsubstituted or substituted by one or more fluorine atoms. A first bed of the at least one bed of anion-exchange adsorbents through which the solution to be purified passes is a bed containing carboxylate ions of formula R--COO.sup.-. Also provided is a plant for the implementation of the inventive process.
Type:
Grant
Filed:
June 3, 1997
Date of Patent:
December 14, 1999
Assignee:
L'Air Liquide, Societe Anonyme pour l'Etude et l'Exploitation des Procedes Georges Claude
Abstract: A process for purifying an aqueous solution of hydrogen peroxide comprising bringing the aqueous solution of hydrogen peroxide into contact with a cation exchange resin or an anion exchange resin, aging the obtained intermediately purified aqueous solution of hydrogen peroxide by standing alone for 1 hour or more, and bringing the aged aqueous solution of hydrogen peroxide into contact with an ion exchange resin of the same type.The process provides a high purity aqueous solution of hydrogen peroxide and can advantageously be used in the field of production of semiconductors.