Including The Addition Of Water Or Steam Patents (Class 203/79)
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Patent number: 5468347Abstract: The present invention provides a method for separating boric acid from a liquid, especially liquid waste obtained from a nuclear power plant. In the process, the waste solution containing the boric acid is contacted with steam in a reactor so that the boric acid evaporates from the liquid and passes into the steam vapor phase. Consequently, the radioactive wastes which are not evaporated with the steam remain in the waste water while the boric acid is removed from the waste water when it passes into the vapor or steam phase. The boric acid can then be separated and recovered from the steam by means of a distillation and fractionating column or a wash column. By removing the boric acid from the liquid waste, it is possible to obtain concentrated radioactive waste having a reduced volume due to the absence of boric acid in the waste.Type: GrantFiled: June 16, 1994Date of Patent: November 21, 1995Assignee: Studiecentrum Voor KernenergieInventors: Aime Bruggeman, Johan Braet
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Patent number: 5399244Abstract: Benzene and other aromatics are separated from a stream of mixed hydrocarbons containing both aromatics and non-aromatics by extractive distillation with a solvent system containing dimethyl sulfoxide and optionally a co-solvent, preferably water, followed by distillation stripping of the aromatics from the enriched solvent system, and recycle of the lean solvent system to the extractive distillation step.Type: GrantFiled: December 6, 1993Date of Patent: March 21, 1995Assignee: Glitsch, Inc.Inventors: Joseph C. Gentry, Lloyd Berg, John C. McIntyre, Randa W. Wytcherley
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Patent number: 5374337Abstract: A halohydrocarbon solvent recovery process. The process in one embodiment includes heating a gross mixture including solvent, fatty-acid impurities and water in a bath to vaporize at least a portion of the solvent and the impurities. A portion of the vapor is then condensed in a reflux condenser to form a condensate mixture. After drying and impurity absorption, a solvent product of at least 99% purity may be recovered. In one embodiment, the gross mixture is obtained from steam stripping dry-cleaner filter cartridges.Type: GrantFiled: August 20, 1993Date of Patent: December 20, 1994Assignee: Technichem Engineering, Ltd.Inventors: Mark J. Ng, Bruce T. Maeda
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Patent number: 5348624Abstract: For separating ETBE and ethanol the following principal stages are employed:(1) Extraction of ethanol by water, the raffinate being ETBE saturated in water and the extract an ethanol/water mixture containing a small proportion of ETBE;(2) Concentration of the above mixture, the distillate being a mixture close to the ethanol/water azeotrope in composition and containing a very small proportion of ETBE;(3) Heteroazeotropic distillation of this distillate in two coupled columns with an overhead decanter, this distillation using ETBE as azeotroping agent; the residue of the first column being ethanol which is ca. 99% by mole and the residue of the second column being practically pure water, this water and the water recovered during the concentration stage being used as extraction solvent in stage (1).Stage (3) may be an ethanol dehydration unit using ETBE as dehydrating agent.Type: GrantFiled: November 12, 1992Date of Patent: September 20, 1994Assignee: Institut Francais du PetroleInventors: Annick Pucci, Paul Mikitenko, Massimo Zuliani
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Patent number: 5264117Abstract: Where side stream distillate strippers are used in the distillation of hydrocarbons, the required size of the distillation column and the amount of stripping gas or vapor required are reduced by passing components stripped from the distillates through a plurality of strippers in series, rather than directly back to the distillation zone.Type: GrantFiled: April 24, 1991Date of Patent: November 23, 1993Assignee: Sun Refining and Marketing CompanyInventor: Gail M. DeLong
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Patent number: 5240566Abstract: A process for separating acetone, dichloromethane and trifluoroacetic acid from a mixture of acetone, dichloromethane, and a trifluoroacetic acid/acetone azeotropeby (1) fractionally distilling the mixture of acetone, dichloromethane, and the trifluoroacetic acid/acetone azeotrope;(2) fractionally distilling the mixture of the trifluoroacetic acid/acetone azeotrope and free acetone;(3) adding at least about 16 parts of water to the trifluoroacetic acid/acetone azeotrope per 100 parts by volume of the trifluoroacetic acid/acetone azeotrope;(4) fractionally distilling the mixture of free acetone and the water/trifluoroacetic acid azeotrope;(5) adding at least about 10 parts of sulfuric acid to the water/trifluoroacetic acid azeotrope per 100 parts by volume of the water/trifluoroacetic acid azeotrope;(6) fractionally distilling the mixture of trifluoroacetic acid and the water/sulfuric acid complex.Type: GrantFiled: December 7, 1992Date of Patent: August 31, 1993Assignee: The Goodyear Tire & Rubber CompanyInventors: Bruce R. Hahn, Thomas R. Maier, Surendra K. Chawla
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Patent number: 5209826Abstract: A steam stripping fraction of sesame seed oil with increased concentration of sesamin and episesamin is used in a molecular distillation process to obtain a fraction containing more than 70 weight % of sesamin and episesamin. The steam stripping fraction is preferably obtained by a steam stripping process wherein the temperature (t.degree. C.) of the sesame seed oil and the pressure (P mmHg) for the process are such that {(4.24.times.10.sup.3)/(9.41-log P)}-273 .ltoreq.t.ltoreq.280 and 0.5.ltoreq.P.ltoreq.20.Type: GrantFiled: July 28, 1992Date of Patent: May 11, 1993Assignee: Takemoto Yushi Kabushiki KaishaInventors: Tatsuhiko Ozaki, Yasunari Hoshii, Hirokazu Matsueda
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Patent number: 5207874Abstract: The purification by distillation of glycidyl (meth)acrylate containing light products containing epichlorohydrin and light impurities, and heavy impurities comprises: in a first stage, a distillation of the glycidyl (meth)acrylate to be purified is conducted in the presence of a first solvent, e.g., water, capable of forming a low boiling point heteroazeotrope with the light impurities and epichlorohydrin, so as to obtain a head fraction which consists essentially of a solvent-light products heteroazeotrope; and, in a second stage, the glycidyl (meth)acrylate thus freed from the light products is subjected to a distillation in the presence of a second solvent, e.g.Type: GrantFiled: June 20, 1991Date of Patent: May 4, 1993Assignee: AtochemInventors: Raymond Hess, Christian Lacroix
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Patent number: 5122234Abstract: This invention is a continuous process for preparing phenol having improved clarity when dispersed in water. The phenol is prepared from crude phenol being the product of decomposition of cumene hydroperoxide and having previously been distilled to remove large portions of acetone, cumene and alphamethyl styrene.Type: GrantFiled: February 4, 1991Date of Patent: June 16, 1992Assignee: Allied-Signal Inc.Inventors: Saul L. Elishewitz, Clifford M. Gilpin, III, Gerald E. Hollenbach, John J. Santarsiero, II, William J. Moffatt, David B. Lebowitz, Dodd S. Smith, Larry B. Wolf
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Patent number: 5092964Abstract: Butter oil is heated under high vacuum and sparged for up to about 6 hours to remove cholesterol. Walls surrounding a vapor space above the sparged mass preferably are heated to remove cholesterol with reduced loss of desirable low molecular weight components. Alternatively, the temperature of the butter oil is lowered, and the butter oil is sparged with steam for an additional period of up to about 3 hours to partially hydrolyze triglycerides to mono- and di-glycerides and free fatty acids. The low cholesterol butter oil then is cooled before being exposed to air, thus avoiding oxidation which produces off-flavors. The resulting low-cholesterol butter fat and products made therefrom have composition and organoleptic characteristics substantially similar to those of natural butter oil and butter.Type: GrantFiled: February 3, 1989Date of Patent: March 3, 1992Assignee: Campbell Soup CompanyInventors: Joseph A. Conte, Jr., Bobby R. Johnson
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Patent number: 5004829Abstract: (CF.sub.3 SO.sub.2).sub.2 O is formed by reaction of CF.sub.3 SO.sub.3 H with P.sub.2 O.sub.5 and taken out of the reaction system by distillation, but the residue of the distillation contains a considerable amount of unreacted CF.sub.3 SO.sub.3 H. From the residue unreacted by adding water or a phosphoric acid solution, preferably the latter, to the residue to obtain a fluidic mixture containing an adequate amount of water and subjecting the mixture to distillation, preferably under reduced pressure at temperatures ranging from 180.degree. to 280.degree. C. It is possible to form additional CF.sub.3 SO.sub.3 H during the recovery process by adding a metal salt of CF.sub.3 SO.sub.3 H to the aformentioned mixture since the metal salt is decomposed by phosphoric acid contained in the mixture.Type: GrantFiled: April 9, 1990Date of Patent: April 2, 1991Assignee: Central Glass Company, LimitedInventors: Minoru Aramaki, Takashi Suenaga, Hiroaki Sakaguchi, Takanori Hamana
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Patent number: 4971661Abstract: An impure propylene oxide feedstock contaminated with from about 50 to about 1000 ppm of methanol and from about 0 to about 1 wt. % of acetone is charged to the lower half of an extractive distillation column containing at least about 25 theoretical plates and an extractive distillation agent consisting essentially of a blend of acetone and water (acetone/water blend) containing about 20 to about 30 wt. % of acetone and, correspondingly, about 80 to about 70 wt. % of water is charged to the tower at a point 4 to 7 theoretical stages above the impure propylene oxide feed point; the extractive distillation agent being introduced into the extractive distillation column in the ratio of said feedstock to said extractive distillation agent of from about 5:1 to about 20:1, whereby an overhead distillate fraction is obtained consisting essentially of propylene oxide contaminated with not more than about 60 ppm of methanol, not more than about 0.02 wt. % of acetone and not more than about 0.3 wt. % of water.Type: GrantFiled: October 20, 1989Date of Patent: November 20, 1990Assignee: Texaco Chemical CompanyInventors: Robert A. Meyer, Kenneth P. Keating, William A. Smith, Robert M. Steinberg
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Patent number: 4892624Abstract: Distillation residues from the purification of caprolactam are worked up by heating in the presence of sodium hydroxide or potassium hydroxide and in the presence of a high-boiling hydrocarbon at from 250.degree. to 500.degree. C. and continuously removing the caprolactam.Type: GrantFiled: August 25, 1988Date of Patent: January 9, 1990Assignee: BASF AktiengesellschaftInventor: Hugo Fuchs
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Patent number: 4863607Abstract: The present invention is a method for using water to remove amine from an oil-amine component. The oil-amine component is typically produced in prior art processes using an amine having an inverse critical solution temperature with water to break emulsions and sludges. The steps of the present invention include adding water to the oil-amine component in an amount sufficient to form a water-amine azeotrope with substantially all the amine in the oil-amine component followed by heating to remove the azeotrope. The method of the present invention may be used to remove amine from an oil-amine component even where the amine is present in an amount as low as 10% or less by weight.Type: GrantFiled: August 3, 1987Date of Patent: September 5, 1989Assignee: Resources Conservation Co.Inventors: John E. Andrew, Howard R. Herrigel, George R. Jones, James C. Nowak, Mark K. Tose, Robert Whalen
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Patent number: 4810330Abstract: Deodorizing and/or physical refining of relatively small, varying charges of high-boiling liquids, viz. fatty acids, edible oils, fats, glycerides and other high-boilding esters, is conducted continuously in a single-stage or multi-stage falling-film column (20) through the trickle passages (23) of which stripping steam is passed in counter-current flow. In the supply conduit (15, 15', 15", 15'") leading to the falling-film column and in the discharge conduit (30, 30', 30", 30'") leading away from the bottom (26) of the falling-film column a plug-flow of the liquid is maintained. Upon a change of charge the fresh liquid to be treated is normally introduced into the supply conduit--without any blank charge--directly following the liquid of the preceding charge. Charging of the liquid onto the deflector (22) in the head (21) of the falling-film column is interrupted for a short period of time when the front of the liquid of the fresh charge has reached a check valve (16) disposed adjacent said deflector.Type: GrantFiled: February 17, 1988Date of Patent: March 7, 1989Inventor: Hermann Stage
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Patent number: 4801356Abstract: Ammonia which is present in fuel cell power plant water in free form, in ionic form, and in forms combined with carbon dioxide, is removed from the power plant water by steam stripping. Water which has been used to cool the fuel reformer effluent, and thus has become contaminated with ammonia, is fed to a first steam stripper wherein a first portion of the ammonia contaminant is removed. The partially stripped water is then fed to a second steam stripper wherein further amounts of ammonia are removed from the water with steam. The ammonia laden steam from the two strippers is combined and vented through a single vent thus conserving the amount of water lost from the system.Type: GrantFiled: October 15, 1987Date of Patent: January 31, 1989Assignee: International Fuel Cells CorporationInventor: Albert P. Grasso
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Patent number: 4778568Abstract: Isomer mixtures of 1,3- and 1,4-bis-(2-hydroxyhexafluoroprop-2-yl)-benzene are separated by a steam distillation in the presence of CS.sub.2. On cooling of the steam distillate, a solid precipitates which is composed mainly of the 1,4-isomer. After the solid has been separated off, an aqueous-organic liquid-phase mixture remains, the organic phase of which mainly contains the 1,3-isomer. The pure isomers are obtained by recrystallization or distillation respectively. These are mainly intermediates in the polymer field.Type: GrantFiled: July 21, 1987Date of Patent: October 18, 1988Assignee: Hoechst AktiengesellschaftInventors: Klaus-Albert Schneider, Gunter Siegemund
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Patent number: 4680092Abstract: The invention concerns a process for the degassing, dehydrating and lower boiling component separation during straight-run distillation of crude fatty acids. The crude fatty acids are degassed in the degassing stage at such temperatures and pressures in counter current flow with stripping steam that no appreciable dehydration or lower boiling component separation takes place at this stage, then the degassed crude fatty acid is then led to a precut column for dehydration and lower boiling component separation, whereby the falling film concentrator column operates as a partial condensation stage for the creation of the reflux of the fatty acids, which is necessary for the lower boiling component separation, and that the easily boiling component evaporates almost completely in the precut column and is led off from the precut column in vapor form, together with the water.Type: GrantFiled: October 5, 1983Date of Patent: July 14, 1987Inventor: Hermann Stage
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Patent number: 4652344Abstract: Dimethoxycyclohexane, prepared by reacting cyclohexanone with methanol, may be recovered from the product mixture in substantially pure form by first adding water as an azeotropic agent to said mixture to form an azeotrope with unreacted cyclohexanone, removing said azeotrope by distillation, thereby leaving substantially pure dimethoxycyclohexane.Type: GrantFiled: December 2, 1985Date of Patent: March 24, 1987Assignee: Sun Refining and Marketing CompanyInventors: Chao-Yang Hsu, Paul E. Ellis, Jr.
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Patent number: 4623447Abstract: Middle phase emulsions are broken by subjecting the emulsion to a first atmospheric distillation step to remove water, followed by a second vacuum distillation step to recover oil. The residue contains the surfactant. The atmospheric distillation is generally carried out by steam distillation.Type: GrantFiled: August 2, 1985Date of Patent: November 18, 1986Assignee: Pennzoil CompanyInventors: Bert H. Clampitt, Asoke K. Deysarkar, Thomas D. Westmoreland, Jr.
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Patent number: 4613410Abstract: A method and apparatus for distilling, especially vacuum refining and deodorizing edible oils and fats utilizing sheets of oil driven downwardly in a distiller with a vacuum source at its top. A nozzle includes pressure equalization chambers, cantilever adjustment screws, and a central drag sheet to produce longer lasting and more uniform thin oil sheets to be driven in the distiller. A continuous process deaerates, dehydrates, degums, bleaches, refines, removes tocopherol, deodorizes, and strips peroxides and hydroperoxides from raw oil in a series of isothermal stages utilizing driven sheet distillers. No stripping steam is used except in the stage which strips peroxides and hydroperoxides. The method produces valuable, pure products such as tocopherol and fractionated fatty acids. It is especially efficient in heat exchange and low in waste and pollution producing products.Type: GrantFiled: October 7, 1983Date of Patent: September 23, 1986Inventor: Jacob B. Rivers, Jr.
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Patent number: 4601790Abstract: Deodorizing and/or physical refining of cocoa butter and cocoa butter substitutes is carried out in accordance with the principle of continuous counter-current falling film stripping steam distillation in at least two different zones, where different flow and current conditions prevail for the liquid film and the vapors, respectively. In the initial zone 10 the vapors pass through trickle passages having a hydraulic equivalent diameter greater than the hydraulic equivalent diameter in the final zone 22.The working pressure in the top of the falling film column 10 is maintained below 2.0 mbar, and in the bottom of the falling film column 22 it is maintained by at most 1.6 mbar in excess of that in the falling film column 10. The accumulation of any significant liquid content in the bottoms of the serially operating zones is avoided. Stripping steam is supplied in an amount of 2 to 10 kg of steam per 100 kg of charged liquid.Type: GrantFiled: July 18, 1983Date of Patent: July 22, 1986Inventor: Hermann Stage
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Patent number: 4599143Abstract: The deodorization and/or physical refining of high-boiling organic edible oils, fats and esters is carried out according to the principle of continuous counter-current falling film stripping steam distillation in an internally imposed temperature field in at least two different zones having different flow conditions for the liquid film and the vapors, respectively, prevailing therein. In the initial zone 10 directly adjacent the liquid charge and ensuring at least two separation stages the vapors flow through trickle passages having a hydraulic equivalent diameter of 73 to 150 mm. If necessary, this initial zone may be subdivided, wherein in the first sub-zone the trickle passages are provided with hydraulic equivalent diameters of 120 to 150 mm and in the second sub-zone the trickle passages are provided with hydraulic equivalent diameters of 73 to 120 mm.Type: GrantFiled: July 18, 1983Date of Patent: July 8, 1986Inventor: Hermann Stage
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Patent number: 4594131Abstract: A water purification process is described for the removal of ammonia and optionally one or more acid gases from wastewaters such as coke-plant or coal conversion wastewaters. The process involves adding alkali to these wastewaters in amounts sufficient to react with fixed ammonia salts present in the wastewater and to enable substantial amounts of the ammonia to be evolved upon distillation, and subjecting the thus treated wastewater to distillation to remove substantial amounts of the ammonia and acid gases present from the wastewater. This process is achieved by two separate and successive distillations. In this process, the vapor streams being withdrawn from the first and/or second distillations are subjected to an impurity removal process to thereby produce a vapor stream substantially reduced in impurities, and useful as a stripping vapor in this process, and then reusing this vapor stream as a stripping vapor in the process.Type: GrantFiled: August 13, 1984Date of Patent: June 10, 1986Assignee: United States Steel CorporationInventor: Edward E. Maier
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Patent number: 4511437Abstract: A process for continuous rectification of a liquid mixture containing alcohols, particularly a liquid fermate, employs a plurality of distillation columns to which the liquid mixture is fed in parallel, and which have successively reduced operating pressures and temperatures from an initial one to a final one thereof. The top vapor distillate from the higher-pressure columns supplies driving heat to the sumps of the next successively lower-pressure columns. Direct steam at 130.degree. C. to 160.degree. C. is fed to the sump of the column operated at the highest pressure. Direct steam is generated by indirect heat exchange of water with the top vapor withdrawn from the columns, and the resulting direct steam is fed to the sumps of the next-lower-pressure columns. The apparatus can also include a section for the production of absolute alcohol.Type: GrantFiled: November 4, 1982Date of Patent: April 16, 1985Assignee: Hoechst AktiengesellschaftInventors: Gunter Heck, Aladar Lienerth, Egon Malow, Karl-Heinz Schwarz, Uwe Faust
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Patent number: 4508597Abstract: A method of recovering light organic solvent from a liquid mixture containing the solvent and a product material, such as asphaltenes or coal liquefaction products. The solvent-product material mixture is treated to separate a first vapor phase rich in solvent and a first liquid phase rich in product material. The first liquid phase is then intimately contacted with steam, under shearing conditions, in a static or dynamic mixer. The steam-liquid phase mixture is then treated to separate a second vapor phase, rich in steam and solvent, and a second liquid phase, rich in product material and substantially depleted of solvent. Solvent is recovered from the first and second vapor phases.Type: GrantFiled: April 5, 1982Date of Patent: April 2, 1985Assignee: Kerr-McGee Refining CorporationInventor: Jack W. Roach
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Patent number: 4434029Abstract: A process for producing an unsaturated nitrile with saved energy by which the bottom stream from a recovery column is used as the heat source for at least one distillation column in the process and thereafter used to pre-heat a recovery column feed withdrawn from the bottom of an absorption column, characterized in that the bottom stream of the absorption column is previously heated by at least one source of waste heat in the process, the source being selected from (1) the circulating water in the quenching column, (2) the overhead vapor of the absorption column, (3) the overhead vapor of a dehydration column and (4) the overhead vapor of a product column.Type: GrantFiled: December 2, 1981Date of Patent: February 28, 1984Assignee: Asahi Kasei Kogyo Kabushiki KaishaInventors: Shigeru Kurihara, Hiroyuki Ohashi
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Patent number: 4323430Abstract: A process for the substantially complete removal of acid gases and ammonia from aqueous solutions is disclosed, which comprises a two stage distillation operation wherein the pressure in the first distillation stage is substantially less than the pressure in the second stage, the ammonia concentration in this stage decreases downwardly so that an aqueous bottoms stream has a pH less than 8, this aqueous bottoms stream is treated with alkali and then distilled in the second stage. A portion of the aqueous bottoms can be vaporized by indirect heat exchange with vapors evolving from the second stage. The improvement lies in adding ammonia to the overhead vapor from the first stage to reduce corrosion of the condenser and preferably, the amount of vapor condensed is controlled to further minimize corrosion.Type: GrantFiled: March 16, 1981Date of Patent: April 6, 1982Assignee: United States Steel CorporationInventors: Donald Glassman, Edward E. Maier
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Patent number: 4311597Abstract: A method of removing ammonia from a wastewater containing free and fixed ammonia said process comprising the steps of: distilling the wastewater to remove the free ammonia; treating the distilled wastewater with soda ash to decompose the fixed ammonia; and distilling the treated wastewater to remove the decomposed ammonia.An apparatus for removing ammonia from a wastewater containing free and fixed ammonia comprising: an ammonia still for removing free and fixed ammonia; a source of soda ash solution; and means for feeding the soda ash solution from said soda ash source to the ammonia still to decompose the fixed ammonia.Type: GrantFiled: February 21, 1979Date of Patent: January 19, 1982Assignees: Republic Steel Corporation, The Hanna Furnace CorporationInventor: Aniruddha Bhattacharyya
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Patent number: 4309254Abstract: A process for the production of alcohol from a fermented feed wherein insoluble organic matter is separated prior to entry into a first distillation column. The insoluble organic matter is dried under pressure to produce dried distillers grain and wherein excess vapor is removed from the drying zone to provide heat to the distillation system. The present process also includes removing excess water vapor from the evaporation zone, obtained from supplemental heating supplied by the overhead from said first distillation column, compressing said water vapor, and recycling it to the distillation columns and the evaporation zone.Type: GrantFiled: April 17, 1980Date of Patent: January 5, 1982Assignee: Stone and Webster Eng. Corp.Inventors: Rodney A. Dahlstrom, Jacob N. Rubin
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Patent number: 4308109Abstract: Process for purifying crude ethanol, whether produced by fermentation or by the synthetic route, to produce a pure ethanol-water azeotrope. The process uses only two distillation columns for fermentation ethanol and only three columns for synthetic ethanol because the latter has diethyl ether as impurity. The inventive concept lies in the design and specification of the columns and the specific distillation conditions which enable each of the impurities in ethanol to be reduced below 1 ppm. Ethanol of such purity is most desirable when used for potable or pharmaceutical purposes. The crude ethanol is fed into a first column and water is separately fed there as well, a side stream of purified aqueous ethanol is withdrawn from the first column and fed to a rectification column where a substantially pure ethanol-water azeotrope is withdrawn as a side stream. The points of introduction and removal of the respective streams to and from the columns are critical for a successful operation and product recovery.Type: GrantFiled: June 17, 1980Date of Patent: December 29, 1981Assignee: BP Chemicals LimitedInventors: Michael J. Griffiths, Arthur E. Jenkins
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Patent number: 4302298Abstract: Process for isolating methyl tert-butyl ether contained in the reaction product of methanol with a C.sub.4 hydrocarbon cut containing isobutene, comprising fractionating said reaction product by introducing it at an intermediate point of a distillation zone, recovering methyl tert-butyl ether at the bottom thereof and, at the top thereof, a mixture of C.sub.4 hydrocarbons with methanol which is washed with water and condensed and wherefrom is separated a condensed C.sub.4 hydrocarbon fraction, a portion of which is fed back as reflux to the top of the distillation zone and another portion discharged, and separating the remaining water-methanol mixture by distillation.Type: GrantFiled: February 22, 1980Date of Patent: November 24, 1981Assignee: Institut Francais du PetroleInventors: Paul Mikitenko, Lionel Asselineau
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Patent number: 4285778Abstract: 2,2-Dichloro-5-methyl-1,1,1-trifluorohex-4-ene, an intermediate in the synthesis of pyrethroid insecticides, is obtained by continuous distillation, preferably under sub-atmospheric pressure, of a mixture of 5-methyl-2,2,4-trichloro-1,1,1-trifluorohexane, dimethylformamide and lithium bromide, precipitating the chlorofluorocarbons from the distillate with water and separating the desired product from starting material by a further distillation.Type: GrantFiled: May 15, 1980Date of Patent: August 25, 1981Assignee: Imperial Chemical Industries LimitedInventors: John Crosby, Bernard W. H. Terry
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Patent number: 4260462Abstract: A process is described for the removal of acid gases and ammonia from dilute aqueous solutions. This is achieved by two separate and successive distillations. In the first distillation, substantially all of the acid gases and free ammonia are removed. In the second distillation, substantially all of the fixed ammonia is removed. Exemplary aqueous solutions are waste waters from coke oven and coal conversion plants.Type: GrantFiled: May 26, 1978Date of Patent: April 7, 1981Assignee: United States Steel CorporationInventors: William J. Didycz, Donald Glassman, Edward E. Maier, George T. Saniga
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Patent number: 4054493Abstract: Preheated saline water, typically sea or brackish water, is further heated by quanta of steam, passed to it at differential temperatures and pressures and condensed in the saline water. Scale compounds are precipitated and scale-forming bicarbonates decomposed, with the evolution of carbon dioxide, which is gathered and expelled by steam accessory to the quanta of steam. Post-thermal saline water, which is formed, is multistage flash vaporized while self-cooling. The flashed vapors are compressed to form said quanta of steam. After being further cooled while preheating saline water, post-thermal saline water is evaporated in a multistage vapor compression evaporator, producing brine at a high concentration factor. Relative to equilibrium in scale-compound precipitation between 302.degree. F and 347.degree. F, the recovery of fresh water is 70% to 80% for sea water, and 80% to 90% for brackish waters over a wide range of salinity.Type: GrantFiled: July 1, 1976Date of Patent: October 18, 1977Inventor: Paul S. Roller
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Patent number: 4045295Abstract: Dilute sulfuric acid contaminated with acetic acid and hydrogen chloride is purified with the resultant formation of concentrated sulfuric acid and acetic acid. To this end, the contaminated sulfuric acid is heated in a first step to at most 60.degree. C under 25-30 mm Hg so as to expel all of the hydrogen chloride together with minor proportions of acetic acid and water. In a second step, the sulfuric acid is heated to at most 165.degree. C under 20-25 mm Hg so as to distil off the bulk of acetic acid together with water. In a third step, the sulfuric acid is cooled down to 60.degree.-90.degree. C, diluted with 10-30 wieght % of water with agitation and while cooling is continued. Following this, the sulfuric acid is heated to 160.degree.-165.degree. C under 20-25 mm Hg and thereby freed from the water and residual acetic acid.Type: GrantFiled: June 10, 1976Date of Patent: August 30, 1977Assignee: Hoechst AktiengesellschaftInventors: Stefan Schafer, Alexander Ohorodnik, Klaus Gehrmann, Albert Mainski
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Patent number: 4043874Abstract: The constituents of an exhausted toluene-dimethylformamide solvent mixture used for removing polyvinyl chloride deposits from polymerization reactors, are separated by adding water to said mixture and distilling off toluene, thereby to obtain a distillation residue having a water content of at least 2 wt.% and a toluene content not exceeding 10 wt.%, precipitating the polymer by cooling the distillation residue, adding a further amount of water, distilling off any toluene present, recovering the precipitate and distilling the residual aqueous solution to recover the dimethylformamide.Type: GrantFiled: December 16, 1976Date of Patent: August 23, 1977Assignee: Societa' Italiana Resine S.I.R. S.p.A.Inventors: Francesco Testa, Antonio Bigliani
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Patent number: 4036865Abstract: A liquid feed stock containing oil is deodorized in a semicontinuous process wherein the feed stock, in a first evacuated chamber, undergoes heat exchange with a deodorized stock in a second evacuated chamber, said stocks being circulated in their respective chambers by upwardly flowing steam introduced into each chamber between a partition, separating the two chambers, and a guide plate parallel to said partition and spaced therefrom, whereafter said feed stock is passed through a succession of steam heating stages to heat said feed stock to successively higher temperatures thereby deodorizing the feed stock and then withdrawn as deodorized stock and recirculated as deodorized stock to said second evacuated chamber to undergo heat exchange with said feed stock.Type: GrantFiled: October 28, 1975Date of Patent: July 19, 1977Assignee: Metallgesellschaft AktiengesellschaftInventors: Albert Hartmann, Herbert Schilken, Bernhard Romeiser
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Patent number: 4014903Abstract: A process for treating an adipic acid bleed stream obtained in the manufacture of adipic acid, said adipic acid bleed stream consisting mainly of nitric, adipic, glutaric, and succinic acids and a catalyst; the process comprising maintaining said adipic acid bleed stream in aqueous solution, and stripping nitric acid from said aqueous solution with steam at a temperature of about 100.degree.-110.degree. C. while maintaining in said aqueous solution a water to nitric acid weight ratio of at least 6, to remove substantially all of the nitric acid therefrom, thereby forming an aqueous nitric acid free mixture of said dibasic acids and said catalyst which can be safely dehydrated and distilled to produce useful chemicals.Type: GrantFiled: August 11, 1975Date of Patent: March 29, 1977Assignee: Allied Chemical CorporationInventor: William Percy Moore
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Patent number: 3957880Abstract: Methacrolein is recovered from a crude gaseous mixture in a process comprising the steps of first absorbing the methacrolein from the mixture with a selective solvent to form a liquid mixture and thereafter subjecting the thus formed liquid mixture to an extractive distillation with water.Type: GrantFiled: January 3, 1974Date of Patent: May 18, 1976Assignee: Nippon Zeon Co., Ltd.Inventors: Ryozi Sato, Takanori Musha, Yoshio Ito
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Patent number: 3956074Abstract: A process for the recovery of methylglyoxal acetal from a reaction mixture which has been obtained in the reaction of acetone with an alcohol and a nitrosation agent or oxidizing agent in the presence of an acid catalyst followed by neutralization which comprises diluting the neutralized reaction mixture with such an amount of water that a homogeneous solution is formed, subsequent distillation in a first column in which a mixture of acetone, alcohol and solvent is removed overhead and returned direct to the synthesis and an azeotrope of methylglyoxal acetal, water and high-boilers is withdrawn as a side stream, condensation of the azeotrope thus obtained and separation of the phase rich in methylglyoxal acetal, subsequent distillation of the phase rich in methylglyoxal acetal thus obtained in a second column in which purified methylglyoxal acetal is withdrawn as a side stream and the overhead and bottoms products are returned with the feed to the first column, pure methylglyoxal acetal being obtained as theType: GrantFiled: July 10, 1974Date of Patent: May 11, 1976Assignee: BASF AktiengesellschaftInventor: Knut Bittler
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Patent number: 3951752Abstract: Saline water, typically sea water or brackish water, after deaeration and deoxygenation is preheated, then further heated by steam condensing with the preheated saline water. By the further heating, bicarbonates are thermally decomposed, forming carbon dioxide, while scale compounds, comprising magnesium hydroxide, anhydrite and minor compounds containing silica, iron, alumina, phosphate, etc., are thermally precipitated. Some of the steam is uncondensed and issues from the further heated saline water with included, evolved carbon dioxide. It is condensed in preheating saline water; evolved carbon dioxide is separated from the condensate and recycled to the saline water to prevent alkaline scale in preheating, while condensate is combined with the further heated saline water, forming post-thermal saline water. This is flash vaporized while cooling and the steam is regenerated by compressing the flashed vapors.Type: GrantFiled: August 13, 1973Date of Patent: April 20, 1976Inventor: Paul S. Roller