Purification Or Recovery Patents (Class 570/262)
-
Patent number: 6534688Abstract: A process is provided for the stabilization of polychlorinated alkanes against dehydrochlorination. The process comprises adding a phenol compound to a polychlorinated alkane such that the dehydrochlorination of the polychlorinated alkane is suppressed when heated in the presence of iron(III). In a preferred embodiment, the process comprises the prevention or reduction of dehydrochlorination of 1,1,1,3,3-pentachloropropane when heated in the presence of iron(III) contamination by the addition of monomethyl ether hydroquinone. In another embodiment, the long term storage stability of polychlorinated alkanes against dehydrochlorination is improved due to the addition of a phenol compound.Type: GrantFiled: June 11, 2001Date of Patent: March 18, 2003Assignee: Vulcan ChemicalsInventor: Rodney L. Klausmeyer
-
Patent number: 6423189Abstract: A process for the preparation of 1,3-dichloropropane by reacting bis(3-hydroxypropyl)ether with hydrogen chloride, optionally in the presence of tertiary basic nitrogen compounds or other tertiary aliphatic bases as catalysts, distilling off the 1,3-dichloropropane and the water of reaction and working up the two phases.Type: GrantFiled: May 30, 2000Date of Patent: July 23, 2002Assignee: Degussa AGInventor: Manfred Kaufhold
-
Publication number: 20020072639Abstract: A process for the crystallisation of a sterically hindered organic compound from a saturated or supersaturated solution of said compound in a solvent therefor, characterised in that crystallisation is effected under elevated pressure at a temperature above the boiling point of said solution at atmospheric pressure and up to the boiling point of said solution at said elevated pressure.Type: ApplicationFiled: November 13, 2001Publication date: June 13, 2002Applicant: NYCOMED IMAGING ASInventor: Jan Cervenka
-
Publication number: 20020035303Abstract: Sample processing methods that utilize a graphitised carbon matrix are useful for determining the relative amounts polyhalogenated biphenyis (PHBs), polyhalogenated dibenzofurans (PHDFs), and polyhalogenated dibenzo-p-dioxins (PHDDs) in a mixture of polyhalogenated diaromatic hydrocarbons (PHDHs). The methods are particularly useful when used in conjunction with cell-based assays for determining the toxicity of PHDH compounds.Type: ApplicationFiled: June 1, 2001Publication date: March 21, 2002Inventors: Michael D. Chu, George C. Clark
-
Publication number: 20020032357Abstract: Removal of water in a vinyl chloride monomer purification system is achieved through (1) providing a distillation column for separation of a liquid admixture of vinyl chloride, hydrogen chloride, and water into (a) an essentially pure vinyl chloride product stream and (b) a hydrogen chloride distillate stream; and (2) placing a drying system in fluid communication with the distillation column midsection at a connection point where the water is at sufficient concentration to provide a useful mass transfer flux of water from a withdrawn midsection stream into a drying agent.Type: ApplicationFiled: September 25, 2001Publication date: March 14, 2002Inventors: Wayne A. Lockhart, Terrence M. Nimchuk, Joseph J.D. Brochu, Ralph Smeding
-
Patent number: 6323380Abstract: Removal of water in a vinyl chloride monomer purification system is achieved through (1) providing a distillation column for separation of a liquid admixture of vinyl chloride, hydrogen chloride, and water into (a) an essentially pure vinyl chloride product stream and (b) a hydrogen chloride distillate stream; and (2) placing a drying system in fluid communication with the distillation column midsection at a connection point where the water is at sufficient concentration to provide a useful mass transfer flux of water from a withdrawn midsection stream into a drying agent.Type: GrantFiled: April 20, 2000Date of Patent: November 27, 2001Assignee: The Dow Chemical CompanyInventors: Wayne A. Lockhart, Terrence M. Nimchuk, Joseph J. D. Brochu, Ralph Smeding
-
Patent number: 6320087Abstract: An adsorbing and separating agent for halogenated aromatic compounds and an adsorbing and separating method for the compounds, using an adsorbent which has a porosity of from 0.20 cc/cc to 0.37 cc/cc, a packing density of from 0.50 g/ml to 0.70 g/ml, and a grain size of from 0.1 mm to 1.0 mm.Type: GrantFiled: April 6, 1999Date of Patent: November 20, 2001Assignee: Toray Industries, Inc.Inventors: Kazuyoshi Iwayama, Shinobu Yamakawa, Masashi Kato, Hirohito Okino
-
Publication number: 20010007048Abstract: The invention provides an adsorbing and separating agent for halogenated aromatic compounds, and an adsorbing and separating method for the compounds. Using the adsorbing and separating agent of the invention gives a high-purity, halogenated aromatic compound isomer. In the adsorbing and separating method of the invention, the adsorbent used is prevented from being deteriorated and its life can be prolonged. The adsorbent for separating halogenated aromatic compounds of the invention has a porosity o from 0.20 cc/cc to 0.37 cc/cc, a packing density of from 0.50 g/ml to 0.70 g/ml, and a grain size of from 0.1 mm to 1.0 mm. With the adsorbent, a halogenated aromatic compound isomer is separated and recovered; or a halogenated aromatic compound having a dissolved oxygen content of at most 15 ppm by weight is separated and recovered with an adsorbent. In the method, at least one, high-purity isomer can be efficiently separated and recovered from a mixture of halogenated aromatic compound isomers.Type: ApplicationFiled: April 6, 1999Publication date: July 5, 2001Inventors: KAZUYOSHI IWAYAMA, SHINOBU YAMAKAWA, MASASHI KATO, HIROHITO OKINO
-
Patent number: 6229059Abstract: Using a process for the production of 1,2-dichloroethane by reacting ethylene and chlorine in the liquid phase in the presence of a catalyst, the 1,2-dichloroethane produced being drawn off in the gaseous phase, the high-boilers being separated from the 1,2-dichloroethane in a heavy-ends column and in a downstream vacuum column and the light-boilers and gases, such as ethylene and hydrogen, being separated in an EDC stripping column or in a light-ends column, a commercial-scale solution should be created to effectively remove the hydrogen chloride at the head of the stripping column or light-boiling column to avoid corrosion occurring there. This is achieved in that the cleaned 1,2-dichloroethane leaving the heavy-ends column is cleaned in the EDC stripping column or in the light-ends column by separating the light-boilers and the gases.Type: GrantFiled: February 4, 2000Date of Patent: May 8, 2001Assignee: Krupp Uhde GmbHInventor: Joachim Motz
-
Patent number: 6150573Abstract: 1,1,1-Trichloroethane (viz., methylchloroform) and 1,1,2-trichloroethane are produced in the same reactor by feeding molecular chlorine and chloroethene (viz., vinyl chloride) as well as 1,1-dichloroethane to the reactor. The ratios at which the two trichloroethanes are produced can be easily controlled by controlling the relative ratios of 1,1-dichloroethane and chloroethene introduced to the reactor. The reactions are conducted in the liquid phase in the presence of free radical initiator.Type: GrantFiled: January 5, 1995Date of Patent: November 21, 2000Assignee: PPG Industries Ohio, Inc.Inventors: Tommy G. Taylor, J. Douglas Mansell, John P. Shamburger, Mark E. Woodyear
-
Patent number: 6121506Abstract: Energetic materials, such as nitrocellulose, TNT, RDX, and combinations thereof, optionally in combination with chemical warfare agents, such as mustard gas, Lewisite, Tabun, Sarin, Toman, VX, and combinations thereof, are destroyed when chemically reacted according to the method of the invention. The method comprises reacting the energetic materials and chemical warfare agents, of present, with solvated electrons which are preferably produced by dissolving an active metal such as sodium in a nitrogenous base such as anhydrous liquid ammonia.Type: GrantFiled: June 10, 1999Date of Patent: September 19, 2000Assignee: Commodore Applied Technologies, Inc.Inventors: Albert E. Abel, Robert W. Mouk, Gerry D. Getman, Wood E. Hunter
-
Patent number: 6101818Abstract: A method for separating water from a chemical mixture is provided. In the process of the invention, water is separated from a chemical mixture by contacting the chemical mixture with a water-soluble polymer.Type: GrantFiled: November 10, 1997Date of Patent: August 15, 2000Assignee: AlliedSignal Inc.Inventors: Raymond Hilton Percival Thomas, Rajiv Ratna Singh, Jeffrey Warren McKown, Roy Phillip Robinson, Stephen Alan Cottrell
-
Patent number: 6093286Abstract: A process for purifying at least 90% pure n-butyl chloride which is present in a mixture with other C.sub.1 to C.sub.4 alkyl chlorides, C.sub.1 to C.sub.4 alcohols, esters, ketones, nitrites, and organic sulfur compounds. In this process the mixture is first distilled, with high-boilers being separated off, and then washed in a plurality of stages with water and with dilute alkali metal hydroxide solution, and, optionally, an aqueous solution of H.sub.2 O.sub.2. In this manner, even a typical impurities may be separated off and a >99% pure product may be obtained.Type: GrantFiled: May 28, 1998Date of Patent: July 25, 2000Assignee: Huels AktiengesellschaftInventors: Clemens Osterholt, Josef Metz, Udo Jegelka
-
Patent number: 5998691Abstract: Chemical warfare agents, including vesicants and nerve agents distributed throughout the world, are destroyed when chemically reacted according to the method and utilizing the apparatus of this invention. The method comprises reacting the chemical warfare agents with nitrogenous base, optionally containing solvated electrons which are conveniently produced by dissolving an active metal like sodium in a nitrogenous base such as anhydrous liquid ammonia.Type: GrantFiled: April 16, 1998Date of Patent: December 7, 1999Assignee: Commodore Applied Technologies, Inc.Inventors: Albert E. Abel, Robert W. Mouk, Alan F. Heyduk, Bentley J. Blum, Gerry D. Getman, Mark D. Steskal
-
Patent number: 5914432Abstract: A halogenated compound (I) containing one or more >C.dbd.O, olefinic and/or aromatic >C.dbd.C< groups is hydrogenated for producing a halogenated compound (II) having no or a decreased level of >C.dbd.O, olefinic and/or aromatic >C.dbd.C< groups. In the hydrogenation process a liquid feed stream comprising one or more of these compounds (I) is contacted with a hydrogen-rich gaseous stream and a liquid recycle stream comprising one or more of these compounds (II) in the presence of a catalyst.Type: GrantFiled: March 27, 1997Date of Patent: June 22, 1999Assignee: The Dow Chemical CompanyInventor: Celio Lume-Pereira
-
Patent number: 5882485Abstract: A process for the separation of dimethyl ether and chloromethane in mixturesA process for the separation of dimethyl ether and chloromethane in mixtures by two distillation steps. In the first step, the mixture is subjected to an extractive distillation with water, aqueous salt solutions or organic liquids as extractant, the top product being chloromethane. In the second step, the dimethyl ether is separated from the extractant.Type: GrantFiled: June 23, 1997Date of Patent: March 16, 1999Assignee: Hoechst AktiengesellschaftInventors: Peter Roth, Erhard Leistner, Hans Haverkamp, Wolfgang Wendel, Michael Kleiber
-
Patent number: 5843286Abstract: A process for the preparation and fractionation of a mixture of dimethyl ether and chloromethane by extractive distillation with water as extractant. The mixture is prepared by reacting methanol with hydrogen chloride. It is then subjected to an extractive distillation with water as extractant, resulting in chloromethane as top product. In the next step, the dimethyl ether is removed by distillation and, in another step, the extraction water is separated from the methanol which is still present.Type: GrantFiled: June 23, 1997Date of Patent: December 1, 1998Assignee: Hoechst AktiengesellschaftInventors: Peter Roth, Erhard Leistner, Hans Haverkamp
-
Patent number: 5789633Abstract: The instant invention relates to azeotropic or azeotrope-like compositions of hydrofluoric acid with at least one of 1,1-dichloroethane, 1-chloro-1-fluoroethane and 1,1-difluoroethane. The invention also relates to manufacturing processes for separating hydrofluoric acid from a mixture comprising hydrofluoric acid and one or more of the 1,1-dihaloethane.Type: GrantFiled: March 18, 1996Date of Patent: August 4, 1998Assignee: E. I. du Pont de Nemours and CompanyInventors: Maria U. D. Beug-Deeb, Barry Asher Mahler, Ralph Newton Miller
-
Patent number: 5780695Abstract: A process for saturating an olefin-containing halogenated organic stream to produce saturated halogenated organic compounds while minimizing the hydrodehalogenation of the organic compounds.Type: GrantFiled: October 31, 1995Date of Patent: July 14, 1998Assignee: UOPInventor: Tom N. Kalnes
-
Patent number: 5744669Abstract: A process for the conversion of a halogenated organic stream containing trace quantities of organic nitrates to produce a stream comprising hydrogenated hydrocarbonaceous compounds free from organic nitrates and halogenated organic compounds by means of contacting the feed stream and hydrogen with a selective hydrogenation catalyst in a first hydrogenation zone at hydrogenation conditions to convert the organic nitrates into water-soluble nitrogen compounds while effectively minimizing the production of hydrogen halide compounds. The resulting effluent from the first hydrogenation zone is contacted with an aqueous scrubbing solution to recover at least a portion of the water-soluble nitrogen compounds in order to produce a stream containing halogenated organic compounds and essentially free of nitrogen compounds which is then introduced into a second hydrogenation zone operated at selected hydrogenation conditions to produce water-soluble hydrogen halide compounds and hydrogenated hydrocarbonaceous compounds.Type: GrantFiled: January 30, 1997Date of Patent: April 28, 1998Assignee: UOPInventors: Tom N. Kalnes, George R. Hibel, Chwu-Ching Jan
-
Patent number: 5698750Abstract: Refrigerants, such as Freon.RTM. 12 and other potential ozone depleting substances will be in short supply as their production is phased out, and until existing refrigeration equipment is retrofitted to receive more environmentally friendly refrigerants. Existing supplies of such refrigerants when contaminated with other refrigerants especially hydrofluoroalkanes like Freon 22 can form azeotropes, which are not readily separated by conventional distillation methods, are selectively decomposed in-situ by reacting with aqueous solutions of metal hydroxides or other bases. The remaining non-reacted refrigerant-containing composition is readily recycled by separation and recovery methods from the reaction mixture to provide a reusable refrigerant composition virtually free of contaminating refrigerant.Type: GrantFiled: October 30, 1995Date of Patent: December 16, 1997Assignee: Commodore Laboratories, Inc.Inventors: Robert W. Mouk, Albert E. Abel
-
Patent number: 5672266Abstract: The present invention relates to a process for reducing the chlorine content of an organochlorine compound comprising: introducing into the organochlorine compound, at least one Lewis acid to form a mixture, and contacting the organochlorine compound with the Lewis acid in the mixture in the absence of elemental carbon for a sufficient amount of time to reduce the chlorine content of the organochlorine compound. In another embodiment, a process is described for reducing the chlorine content of an organochlorine compound comprising contacting the organochlorine compound with (a) at least one acid selected from the group consisting of Lewis acids, mineral acids other than hydriodic acid and hydrobromic acid, and organic acids having a pKa of less than about 2, and (b) a source of iodine or bromine in the absence of elemental carbon for a sufficient amount of time to reduce the chlorine content of the organochlorine compound.Type: GrantFiled: October 13, 1995Date of Patent: September 30, 1997Assignee: The Lubrizol CorporationInventors: Matthew R. Sivik, Mohamed G. Fahmy
-
Patent number: 5637782Abstract: A process for saturating an olefin-containing halogenated organic stream to produce saturated halogenated organic compounds while minimizing the hydrodehalogenation of the organic compounds.Type: GrantFiled: December 2, 1994Date of Patent: June 10, 1997Assignee: UOPInventor: Tom N. Kalnes
-
Patent number: 5616821Abstract: Refrigerants, such as Freon.RTM. 12 and other potential ozone depleting substances will be in short supply as their production is phased out, and until existing refrigeration equipment is retrofitted to receive more environmentally friendly refrigerants. Existing supplies of such refrigerants when contaminated with other refrigerants especially chlorofluorohydrocarbons like Freon 22 form azeotropes, which are not readily separated by conventional distillation methods, are selectively decomposed in-situ by reacting with bases such as metal hydroxides in aqueous solutions or compatible organic solvents. The remaining non-reacted refrigerant-containing composition is readily recycled by separation and recovery methods from the reaction mixture to provide a reusable refrigerant composition practically free of contaminating refrigerant.Type: GrantFiled: January 30, 1995Date of Patent: April 1, 1997Assignee: Commodore Laboratories, Inc.Inventors: Robert W. Mouk, Albert E. Abel
-
Patent number: 5602295Abstract: Ozone depleting fluorocarbon compounds are dehalogenated through more economic reduction reaction with solvated electrons formed from lower equivalents of reactive metals than previously used by reacting the partial reduction products with nitrogen-containing bases, such as ammonia, or alternatively, without any reactive metal by reacting with the base alone. Mixtures of fluorocarbon refrigerants including difficult to separate azeotropes of dichlorodifluoromethane contaminated with chlorodifluoromethane are reclaimed by treating only with weak non-aqueous nitrogen-containing bases to provide essentially chemically pure dichlorodifluoromethane refrigerant suitable for recycling/reuse. Hazardous cyanides which may develop are converted to relatively benign products during the process by introducing a base to convert volatile cyanides to more stable salts which in turn are converted to useful compounds of lesser toxicity.Type: GrantFiled: May 5, 1995Date of Patent: February 11, 1997Assignee: Commodore Laboratories, Inc.Inventors: Marc W. Abel, Robert W. Mouk, Alan F. Heyduk, Albert E. Abel
-
Patent number: 5600041Abstract: A process for treating a stream containing halogenated organic compounds and having trace quantities of organic nitrates to produce a stream comprising halogenated organic compounds free from organic nitrates by the utilization of a hydrogenation zone operated at selective hydrogenation conditions in order to convert the organic nitrates to water-soluble nitrogen compounds while minimizing the production of hydrogen halide compounds. The resulting water-soluble nitrogen compounds are removed by extraction with an aqueous stream.Type: GrantFiled: February 13, 1995Date of Patent: February 4, 1997Assignee: UOPInventors: Chwu-Ching Jan, Tom N. Kalnes, George R. Hibel
-
Patent number: 5559278Abstract: Ozone depleting fluorocarbon compounds are dehalogenated through more economic reduction reaction with solvated electrons formed from lower equivalents of reactive metals than previously used by reacting the partial reduction products with non-aqueous liquid nitrogen-containing bases, such as ammonia, or alternatively, without any reactive metal by reacting with the base alone. Mixtures of fluorocarbon refrigerants including difficult to separate azeotropes of dichlorodifluoromethane contaminated with chlorodifluoromethane are reclaimed by treating only with weak non-aqueous nitrogen-containing bases to provide essentially chemically pure dichlorodifluoromethane refrigerant suitable for recycling/reuse.Type: GrantFiled: December 21, 1994Date of Patent: September 24, 1996Assignee: Commodore Laboratories, Inc.Inventors: Robert W. Mouk, Albert E. Abel
-
Patent number: 5536891Abstract: A process for the purification of 1,1,1-trichloroethane contaminated with at least one undesirable C.sub.1 -C.sub.3 chlorocarbon, for example, 1,2-dichloroethane, 1,2-dichloroethylene and/or trichloroethylene, which process comprises contacting the impure 1,1,1-trichloroethane with a particulate adsorbent, the adsorbent being a particulate product of controlled pyrolysis of a polysulfonated macroporous crosslinked vinylaromatic polymer having a surface area of at least about 500 m.sup.2 /g, a micropore pore volume of at least about 0.24 ml/g, a macropore pore volume of less than about 0.24 ml/g and a ratio of macropore to micropore pore volume of less than 100 percent is provided.Type: GrantFiled: June 7, 1994Date of Patent: July 16, 1996Assignee: Vulcan Materials CompanyInventor: William Q. Beard, Jr.
-
Patent number: 5514251Abstract: The invention relates to binary azeotropic compositions between water and 1,1-dichloro-1-fluoroethane, 1-chloro-1,1-difluoroethane, 1,1,1-trifluoroethane, 1,1,1,2-tetrafluoroethane, 1,1-difluoroethane or trifluoroethylene, to a process for the removal of water from solutions by azeotropic distillation using these compositions, as well as to a process for the production of a hydrofluoroalkane in which water is removed from the mixture of reaction products by azeotropic distillation using these compositions.Type: GrantFiled: March 22, 1994Date of Patent: May 7, 1996Assignee: Solvay (Societe Anonyme)Inventors: Dominique Balthasart, Andre Jacquemart
-
Patent number: 5504239Abstract: A first alkanol having from 1 to 3 carbon atoms can be separated off from other organic compounds of higher carbon number from the group comprising other alcohols, polyalcohols, ethers, oxo compounds, esters of carboxylic acids and of carbonic acid, haloaliphatics, amines, amides, hydrocarbons, carboxylic acids and nitriles, which in each case have at least 1 carbon atom more than the first alkanol, where in the case of halogenoaliphatics, halogen substituents are counted as further carbon atoms, by permeation on membranes, if a water content from 1 to 30% by weight, preferably from 5 to 15% by weight, based on the amount of mixture and water, is maintained.Type: GrantFiled: June 7, 1994Date of Patent: April 2, 1996Assignee: Bayer AktiengesellschaftInventors: Wolf Mehl, Wolfgang Scheinert, Ingo Janisch, Andreas Groschl
-
Patent number: 5500097Abstract: The present invention provides a method for removing an organic compound in water at a high efficiency by separating an organic compound, particularly such an organic chlorine compound as 1,2-dichloroethane, carbon tetrachloride and chloroform dissolved in water or forming two liquid phases with water from a water phase, by the steps of:(i) charging water containing an organic compound into a first distillation column for conducting distillation or steam distillation to take the organic compound and water out of the top of the first distillation column and to obtain a bottom liquor containing the organic compound at a lower content from the bottom of the first distillation column, and(ii) charging the bottom liquor of the first distillation column into a second distillation column operated at a pressure lower than that in the first distillation column for conducting distillation, preferably flashing under reduced pressure, to take a gas distillate containing a large amount of the organic compound out of the tType: GrantFiled: December 28, 1994Date of Patent: March 19, 1996Assignee: Mitsubishi Chemical CorporationInventors: Shinji Yamamoto, Kazutoshi Itoyama, Seiichi Fujimaki
-
Patent number: 5489390Abstract: The present invention relates to a process for reducing the chlorine content of an organochlorine compound comprising: introducing into the organochlorine compound, at least one acid selected from the group consisting of Lewis acids, mineral acids other than hydriodic acid and hydrobromic acid, and organic acids having a pKa of less than about 2 to form a mixture, and contacting the organochlorine compound with the at least one acid in the mixture for a sufficient amount of time to reduce the chlorine content of the organochlorine compound.Type: GrantFiled: March 14, 1995Date of Patent: February 6, 1996Assignee: The Lubrizol CorporationInventors: Matthew R. Sivik, Mohamed G. Fahmy
-
Patent number: 5436211Abstract: The invention concerns a process for the recovery of a solvent adsorbed in an adsorber, or other substances which are condensable. The adsorber (3) is, at first, heated to a temperature which is below the decomposition temperature of the solvent, then the adsorber chamber (2) is sealed off from the surroundings and a high negative pressure is applied to the adsorber chamber (2), as a result of which the solvent is desorbed. During a portion of the time when this high negative pressure is applied, the temperature of the adsorber (3) is brought to a value which is above the decomposition temperature of the solvent. In spite of this, there is no decomposition under the noted conditions, however, the high temperature does enable an almost complete desorption of the solvent. Finally, the desorbed solvent is drawn off from the adsorber chamber (2) and condensed.Type: GrantFiled: February 1, 1993Date of Patent: July 25, 1995Assignee: Pero KGInventor: Horst Erbel
-
Patent number: 5436378Abstract: Water-containing mixtures of at least one hydrocarbon/halocarbon and hydrochloric acid, e.g., the methyl chloride feedstream in conventional process for the synthesis of chloromethanes, are desiccated by intimately contacting such mixtures with an effective drying amount of an essentially anhydrous drying agent that includes (i) a metal sulfate, chloride or perchlorate, or (ii) phosphorus pentoxide.Type: GrantFiled: June 21, 1994Date of Patent: July 25, 1995Assignee: AtochemInventors: Jean-Jacques Masini, Elie Ghenassia, Raymond Commandeur, Rene Clair, Jean-Louis Guillaumenq
-
Patent number: 5425854Abstract: Methylene chloride is difficult to separate from tetrahydrofuran by conventional distillation or rectification because of the proximity of their vapor pressures. Methylene chloride can be readily separated from tetrahydrofuran by extractive distillation. Effective agents are 1-pentanol, 1,2-butanediol and 3-nitrotoluene.Type: GrantFiled: January 17, 1995Date of Patent: June 20, 1995Assignee: Lloyd BergInventor: Lloyd Berg
-
Patent number: 5414200Abstract: Ozone depleting fluorocarbon compounds are dehalogenated through more economic reduction reaction with solvated electrons formed from lower equivalents of reactive metals than previously used by reacting the partial reduction products with non-aqueous liquid nitrogen-containing bases, such as ammonia, or alternatively, without any reactive metal by reacting with the base alone. Mixtures of fluorocarbon refrigerants including difficult to separate azeotropes of dichlorodifluoromethane contaminated with chlorodifluoromethane are reclaimed by treating only with weak non-aqueous nitrogen-containing bases to provide essentially chemically pure dichlorodifluoromethane refrigerant suitable for recycling/reuse.Type: GrantFiled: March 7, 1994Date of Patent: May 9, 1995Assignee: A.L. Sandpiper CorporationInventors: Robert W. Mouk, Albert E. Abel
-
Patent number: 5396003Abstract: A process for the recovery and purification of 1,1,2-trichloroethane from the intermediates produced for the production of ioversol for reuse thereof.Type: GrantFiled: May 27, 1993Date of Patent: March 7, 1995Assignee: Mallinckrodt Medical PMCInventor: William Z. McCarthy
-
Patent number: 5324393Abstract: A method for preventing fouling of ethylene dichloride distillation units which comprises treating the feed to such unit with a fouling preventing amount of a composition comprising (a) 2-15 weight % of an oil soluble polyacrylate ester or methacrylate ester with alcohol radical of the ester group containing from C.sub.4 -C.sub.22 carbon atoms which contains between 0.1-25 mole % of amino alcohol ester groups; (b) 20-40 weight % a phenylene diamine compound having the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, and R.sub.4 are the same or different and are hydrogen, C.sub.1 -C.sub.20 alkyl, C.sub.1 -C.sub.20 aryl, C.sub.1 -C.sub.20 alkaryl or C.sub.1 -C.sub.20 aralkyl, with the proviso that at least one of R.sub.1, R.sub.2, R.sub.3 or R.sub.4 is hydrogen; and (c) the balance is a heavy aromatic solvent.Type: GrantFiled: April 15, 1993Date of Patent: June 28, 1994Assignee: Nalco Chemical CompanyInventor: Michael K. Poindexter
-
Patent number: 5288929Abstract: A method for removing, condensing and collecting propellants, e.g. chlorofluoro-carbons (CFCs) in an environmentally friendly manner from foam materials, e.g. insulant materials from old (discarded) refrigerators, district heating tubes and other materials for which the method is suitable.Type: GrantFiled: February 12, 1992Date of Patent: February 22, 1994Assignee: L&E Holding ApSInventor: Lau O. Voers
-
Patent number: 5262014Abstract: A process for removing acetone from an acetone/methyl acetate/methyl iodide mixture utilizing extractive distillation with water being introduced to the distillation zone above the point of introduction of the mixture and acetic acid being introduced at or above the point of introduction of the mixture. In a preferred embodiment the mixture is subjected to an initial extraction with an aqueous extractant to remove most of the methyl iodide.The process is particularly applicable to removing acetone by-product in carbonylation processes for the production of acetic anhydride.Type: GrantFiled: June 12, 1992Date of Patent: November 16, 1993Assignee: The British Petroleum Company p.l.c.Inventors: Jeremy B. Cooper, John Dixon-Hall, Stephen J. Smith
-
Patent number: 5262057Abstract: A process for separating from one another non-functional, monofunctional and bifunctional species in a mixture of perfluoropolyoxyalkylenes of general formulaX--O--Rf--Ywhere:Rf=a perfluoropolyoxyalkylene chain comprising monomeric units of formulas (CF.sub.2 O), (CF.sub.2 CF.sub.2 O), (CF.sub.2 CF.sub.2 CF.sub.2 O),X, Y, like or different from each other, are non-functional end groups or end groups containing functions OH and/or NH.sub.2,which consists in subjecting said mixture of perfluoropolyoxyalkylenes to column chromatography using, as eluents, non-polar fluorinated solvents, either alone or in admixture with polar solvents.Type: GrantFiled: October 19, 1992Date of Patent: November 16, 1993Assignee: Ausimont S.p.A.Inventors: Claudio Tonelli, Stefano Turri, Giuseppe Gianotti, Marinella Levi
-
Patent number: 5246588Abstract: A process for separating, or enriching, non-functional, monofunctional and bifunctional species in a mixture of perfluoropolyoxyalkylenes of the general formula:Z--O--Rf--YwhereRf=a perfluoropolyoxyalkylene chain comprising one or more monomeric units of formula ##STR1## --CFXO-- (X=F, CF.sub.3), and optionally also units (--CF.sub.2 CF.sub.2 O--); andZ, Y, like or different from each other, are non-functional groups or functional groups containing --OH,which consists in subjecting said mixture of perfluoropolyoxyalkylenes to column chromatography using, as eluents, non-polar fluorinated solvents, either alone or in admixture with polar solvents.Type: GrantFiled: October 20, 1992Date of Patent: September 21, 1993Assignee: Ausimont S.p.A.Inventors: Claudio Tonelli, Stefano Turri, Marinella Levi, Giuseppe Gianotti
-
Patent number: 5211020Abstract: A method for separating HFA 134a from an HFA 134a-rich mixture thereof with HF and/or CFC 1122 which comprises feeding the mixture to a distillation column to separate an azeotrope or near-azeotrope of HFA 134a and HF and/or CFC 1122 from a residue comprising substantially pure HFA 134a. Starting from an HF-rich mixture of HFA 134a such as a typical product stream in HFA 134a production, the method includes a first distillation step to separate HF from the initial mixture and produce an azeotrope or near azeotrope of HFA 134a and HF which is an HFA 134a-rich mixture.Type: GrantFiled: July 2, 1991Date of Patent: May 18, 1993Assignee: Imperial Chemical Industries, PLCInventors: Andrew M. Taylor, Robert W. Wheelhouse
-
Patent number: 5207876Abstract: Tetrachloroethylene cannot be completely separated from methanol, ethanol, 1-propanol, isopropanol, 1-butanol, 2-butanol, isobutanol, 1-pentanol, 2-pentanol, 3-methyl-1-butanol or t-amyl alcohol by conventional distillation or rectification because of the minimum boiling azeotropes. Tetrachloroethylene can be readily separated from these alcohols by extractive distillation. A typical effective agent is dimethylsulfoxide.Type: GrantFiled: January 17, 1992Date of Patent: May 4, 1993Assignee: Lloyd BergInventors: Lloyd Berg, Zuyin Yang
-
Patent number: 5198121Abstract: Water-containing mixtures of at least one hydrocarbon/halocarbon and hydrochloric acid, e.g., the methyl chloride feedstream in conventional process for the synthesis of chloromethanes, are desiccated by intimately contacting such mixtures with an effective drying amount of an essentially anhydrous drying agent that includes (i) a metal sulfate, chloride or perchlorate, or (ii) phosphorus pentoxide.Type: GrantFiled: November 26, 1991Date of Patent: March 30, 1993Assignee: AtochemInventors: Jean-Jacques Masini, Elie Ghenassia, Raymond Commandeur, Rene Clair, Jean-Louis Guillaumenq
-
Patent number: 5196094Abstract: 1,1,1-Trichloroethane cannot be completely separated from methanol, ethanol, n-propanol, isopropanol, 2-butanol or t-butanol by conventional distillation or rectification because of the minimum boiling azeotropes. 1,1,1-Trichloroethane can be readily separated from these alcohols by extractive distillation. A typical effective agent is dimethylsulfoxide.Type: GrantFiled: November 8, 1991Date of Patent: March 23, 1993Assignee: Lloyd BergInventors: Lloyd Berg, Zuyin Yang
-
Patent number: 5196579Abstract: The invention relates to a process for the recovery of perfluoroethercarboxylic acids from the crude product of the electrochemical conversion of these acids or of one of their soluble salts to perfluorinated ethers, in which the perfluoroethercarboxylic acids and their esters contained in the crude product are separated off with the aid of a solid basic alkali metal salt or its solution and converted, by reaction of the resulting salts with a strong acid, to the corresponding perfluoroethercarboxylic acids.Type: GrantFiled: December 13, 1991Date of Patent: March 23, 1993Assignee: Hoechst AGInventors: Thomas Gries, Klaus-Dieter Ginzel, Frank Ebmeyer
-
Patent number: 5175381Abstract: A method for recovering halogenated hydrocarbons (FCH) from synthetic foams wherein halogenated hydrocarbons (FCH) are released from synthetic foam in a hermetically sealed processing chamber and transferred to a gaseous carrier medium of steam. The steam/FCH mixture is removed from the processing chamber and subjected to condensation to remove pure FCH from the condensed water.Type: GrantFiled: July 29, 1991Date of Patent: December 29, 1992Assignee: SMG Sommer Metallwerke GmbHInventors: Heinz Hoberg, Joachim Christiani, Martin Bender
-
Patent number: 5160585Abstract: Tetracholorethylene cannot be completely separated from n-butanol, isobutanol or 2-butanol by conventional distillation or rectification because of minimum boiling azeotropes. Tetrachloroethylene can be readily separated from n-butanol, isobutanol or 2-butanol by extractive distillatiion. Typical effective agents are: for n-butanol, dipropylene glycol methyl ether; for isobutanol, dimethylsulfoxide and isobutyl butyrate; for 2-butanol, ethylene glycol methyl ether and isobornyl acetate.Type: GrantFiled: July 23, 1991Date of Patent: November 3, 1992Assignee: Lloyd BergInventor: Lloyd Berg
-
Patent number: 5152876Abstract: Methylene chloride cannot be completely separated from methanol or ethanol by conventional distillation or rectification because of the mimimum boiling azeotrope. Methyelne chloride can be readily separated from methanol or ethanol by azeotropic or extractive distillation. Typical effective agents are: for methanol by azeotropic distillation, isopropanol or t-butanol; by extractive distillation, 1-nitropropane or n-butanol; for ethanol by extractive distillation, isobutanol or n-propyl acetate.Type: GrantFiled: March 27, 1991Date of Patent: October 6, 1992Assignee: Lloyd BergInventors: Lloyd Berg, Zuyin Yang