By Adsorption Or By Chemical Reaction With Impurity Patents (Class 549/542)
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Patent number: 5000825Abstract: A method is provided for the separation by extractive distillation of oxygenated impurities from a monoepoxide while avoiding epoxide loss, wherein lower glycol is used as extractive solvent in amounts so as to provide only up to about 0.3 mol % solvent in the vapor in the extractive distillation zone.Type: GrantFiled: June 6, 1990Date of Patent: March 19, 1991Assignee: Arco Chemical Technology, Inc.Inventors: T. Thomas Shih, John C. Jubin, Jr.
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Patent number: 4983260Abstract: A process for the concentration of ethylene oxide in an impure solution thereof including adding the solution and steam to a distillation column, recovering the gaseous stream therefrom containing ethylene oxide, and progressively condensing the steamed solution in at least two heat exchangers arranged in series, with the absolute pressure of the distillation column and of the exchangers being between about 1.5 and 6 bars and the temperature of the cooling fluid of the last exchanger being between about 5.degree. C. and a maximum temperature 5.degree. C. below the temperature of condensation of pure ethylene oxide at the pressure used.Type: GrantFiled: April 3, 1989Date of Patent: January 8, 1991Inventors: Henri Neel, Francis DeLannoy
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Patent number: 4935101Abstract: Water-insoluble crystallizable epoxy alcohols such as phenyl glycidol are recovered from epoxidation reaction mixtures by washing the mixture with water, concentrating the mixture by distillation under vacuum to remove unreacted hydroperoxide and alcohol co-product, and crystallizing the epoxy alcohol from solution. Minimal decomposition of the epoxy alcohol is observed.Type: GrantFiled: October 13, 1989Date of Patent: June 19, 1990Assignee: Arco Chemical Technology, Inc.Inventors: Wilfred P. Shum, Christopher J. Sowa
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Patent number: 4831196Abstract: A high efficiency process for removal and detoxification of olefin oxides from gas compositions is described. The process consists of olefin oxide absorption at ambient pressure in an absorber using an aqueous liquid as the absorbing medium and subsequent hydrolysis of the olefin oxide to products including an alkylene glycol in a chemical reactor operating at a controlled temperature and pH in the presence of an acid catalyst. The absorption stage is favored by low temperature and high liquid to gas ratios. More than 99% of an olefin oxide contained in a gas stream can be effectively removed in the absorption stage. The hydrolysis stage is favored by low pH conditions. More than 99% of the incoming olefin oxide to the reactor can be converted to alkylene glycols. The process has a capability of removing and detoxifying olefin oxide from gas streams with an overall effectiveness exceeding 98%. The process also provides for recovering inert diluent contained in the gas compositions.Type: GrantFiled: April 5, 1988Date of Patent: May 16, 1989Assignee: Chemrox, Inc.Inventors: Anthony J. Buonicore, Pankaj R. Desai
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Patent number: 4772732Abstract: The invention discloses a method for purifying butylene oxide by using an anion exchange resin and an adsorbent. The anion exchange resin removes acid and aldehyde impurities while the adsorbent removes water impurities from the butylene oxide. Depending upon the impurity level, the purification steps can be conducted singularly or in combination, and the process can proceed either batchwise in a reactor or continuously in a column. The ion exchange resin of the choice is a sulfonated macroreticular anion exchange resin and the adsorbent of choice is a molecular sieve.Type: GrantFiled: May 8, 1986Date of Patent: September 20, 1988Assignee: BASF CorporationInventors: Mao Y. Huang, Lawrence E. James, Joseph F. Louvar, Ernst Langer
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Patent number: 4692535Abstract: Process for improving the quality of propylene oxide contaminated with minute quantities of high molecular weight poly(propylene oxide) by contacting liquid propylene oxide with certain solid adsorbents, such as activated carbon and attapulgite, thereby obtaining a substantially pure oxide product essentially free of high molecular weight poly(propylene oxide) suitable for conversion of polyether polyols capable of producing high resilient flexible polyurethane foams exhibiting high rise and substantially free of blow hole formation.Type: GrantFiled: December 22, 1986Date of Patent: September 8, 1987Assignee: Atlantic Richfield CompanyInventors: Harold V. Larson, Hyman D. Gillman
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Patent number: 4691034Abstract: Methyl formate is removed from propylene oxide by treatment with aqueous calcium hydroxide slurry. Calcium hydroxide solubility is increased by adding a solubilizer selected from the group consisting of sucrose, fructose, maltose, glycerol and mixtures thereof. Methyl formate hydrolysis rate is improved by propylene oxide/water ratio control. Addition of an aldehyde scavenger improves propylene oxide purity.Type: GrantFiled: April 14, 1986Date of Patent: September 1, 1987Assignee: Texaco, Inc.Inventors: John R. Sanderson, William A. Smith, Edward T. Marquis, Kenneth P. Keating
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Patent number: 4691035Abstract: Methyl formate is removed from propylene oxide by treatment with a selected base such as sodium hydroxide in water and glycerol. Selected inert salts may be added. The rate of methyl formate hydrolysis by selected bases was increased to commercially acceptable levels by addition of the glycerol. The glycerol and inert salts reduced the amount of residual water in the propylene oxide.Type: GrantFiled: April 14, 1986Date of Patent: September 1, 1987Assignee: Texaco Inc.Inventors: John R. Sanderson, Edward T. Marquis, William A. Smith, Kenneth P. Keating
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Patent number: 4668807Abstract: To reduce the content of hydrolyzable chlorine in glycidyl compounds, these are dissolved in a halogen-free organic solvent and treated with an equivalent excess of aqueous alkali metal hydroxide solution at elevated temperature, the excess being 100 to 200% of the equivalent amount theoretically required for complete dehydrochlorination of the hydrolyzable chlorine, the water is then removed from the organic solution, the organic solution is treated with 5 to 500 times the amount, based on the amount of alkali metal hydroxide employed, of moist cellulose containing up to 35% by weight of water at elevated temperature and, after filtration, the glycidyl compound is isolated from the organic solution.Type: GrantFiled: December 11, 1985Date of Patent: May 26, 1987Assignee: Ciba-Geigy CorporationInventors: Jacques Darbellay, Gerald Dessauges
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Patent number: 4617357Abstract: To reduce the content of chlorine in glycidyl compounds, in which the glycidyl groups are bonded to ether-oxygen, N or S atoms, these compounds are dissolved in a halogen-free inert organic solvent and reacted with a tin hydride of the formula I or IIR.sub.3 SnH (I)orR.sub.2 SnH.sub.2 (II)in which each radical R independently of one another is alkyl with 1 to 4 C atoms or phenyl, at least 1 equivalent of the tin hydride of the formula I or II being employed per equivalent of chlorine present, in the presence of a catalytic amount of an initiator which forms free radicals. The glycidyl compounds are then isolated from the reaction solution.Type: GrantFiled: September 16, 1985Date of Patent: October 14, 1986Assignee: Ciba-Geigy CorporationInventors: Kemal D. Pallie, Gerald Dessauges
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Patent number: 4535150Abstract: Low hydrolyzable chlorine containing epoxy resins are obtained by conducting a second dehydrohalogenation of the resin in isopropanol or secondary butanol solvent using aqueous alkali metal hydroxide as the dehydrohalogenating agent. Low hydrolyzable chlorine containing epoxy resins when cured have excellent electrical resistance properties.Type: GrantFiled: December 4, 1984Date of Patent: August 13, 1985Assignee: Celanese CorporationInventor: Joe M. Hunter
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Patent number: 4511710Abstract: Unwanted halogen values are removed from liquid resin, organic or hydrocarbon material by adding particulate crystalline lithium aluminate compounds to the liquid material to act as a halogen scavenger, then separating the crystalline aluminate compound from the liquid material.Type: GrantFiled: June 11, 1984Date of Patent: April 16, 1985Assignee: The Dow Chemical CompanyInventors: Chun S. Wang, Kyle B. Benkendorfer, John L. Burba, III
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Patent number: 4423239Abstract: In a method for purifying a crude epoxidation product of a liquid conjugated diolefin polymer or a vegetable oil which comprises the steps of adding an aqueous washing agent to a crude epoxidation product which is obtained by the reaction of a liquid conjugated diolefin polymer or a vegetable oil with an organic peracid or an epoxidizing agent capable of generating an organic peracid in situ, stirring the mixture, leaving the mixture to stand to induce phase separation and thereafter withdrawing the organic layer, the improvement wherein 50 to 300 parts by weight, per 100 parts by weight of the crude epoxidation product, of a 10-80% by weight aqueous solution of isopropanol is used as the washing agent.Type: GrantFiled: September 28, 1982Date of Patent: December 27, 1983Assignee: Nippon Petrochemicals Company, LimitedInventors: Kazuo Miyazaki, Hajime Hara, Kojiro Teramoto, Hideo Horii, Humiaki Oshimi, Yoshihiko Araki