Purification Or Recovery Patents (Class 568/748)
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Patent number: 5847234Abstract: 4-Hydroxybiphenyl is obtained in non-thixotropic form if a reaction mixture which is obtained by alkaline hydrolysis of biphenyl-4-sulfonic acid and contains 4-hydroxybiphenyl is heated at elevated pressure at above 115.degree. C. and at a pH from 0 to below 6.5.Type: GrantFiled: June 12, 1997Date of Patent: December 8, 1998Assignee: Bayer AktiengesellschaftInventors: Horst Behre, Helmut Fiege, Gunter Rauchschwalbe
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Patent number: 5510543Abstract: The present invention is an improved method for the recovery of phenol from a cleavage mass resulting from the sulfuric acid cleavage of cumene hydroperoxide comprising neutralizing the cleavage mass, forming an aqueous phase and an organic phase, separating the organic phase into an acetone-rich stream and a phenol-rich stream, removing phenol tars from the phenol-rich stream and cracking the phenol tars wherein the improvement comprises maintaining the pH of the cleavage mass during neutralization between 4.0 and about 4.9 whereby the sulfuric acid is converted to the bisulfate salt and substantially no free sulfuric acid remains in the cleavage mass and corrosion of process equipment is reduced.As a result of this improved process, a phenol tar waste stream containing less than about 4 parts per million by weight of chromium is obtained.Type: GrantFiled: December 9, 1994Date of Patent: April 23, 1996Assignee: General Electric CompanyInventors: John W. Fulmer, Andrei K. Griaznov, William D. Kight, Vladimir M. Zakoshansky
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Patent number: 5304689Abstract: Para-cumylphenol is continuously produced by the reaction of purified phenol and alpha-methylatyrene in the presence of an acidic catalyst and an effective amount of hypophosphorous acid (H.sub.3 PO.sub.2) for stabilizing the color and UV absorption.Type: GrantFiled: April 5, 1993Date of Patent: April 19, 1994Assignee: General Electric CompanyInventor: Gaylord M. Kissinger
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Patent number: 5254750Abstract: A process is described for the removal of guaiacol and substituted guaiacols from naturally occurring cresylic acid feed by heating the feed with a strong base, particularly sodium hydroxide, to produce a purified cresylic acid product essentially free of guaiacol and other methoxy aromatic compounds without significant loss of cresylic acid product.Type: GrantFiled: April 5, 1993Date of Patent: October 19, 1993Assignee: Merichem CompanyInventor: John A. Waters
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Patent number: 5196605Abstract: In a process for the preparation of 4,4'-dihydroxybiphenyl of high purity 4,4'-dibromobiphenyl is hydrolized in the presence of a copper compound catalyst, the insoluble materials comprising the catalyst is filtered off from the product mixture, 4,4'-dihydroxybiphenyl is precipitated by adjusting the pH and crude 4,4'-dihydroxybiphenyl separated from the product mixture is fractionally distilled to obtain substantially pure 4,4'-dihydroxybiphenyl.Type: GrantFiled: May 28, 1991Date of Patent: March 23, 1993Assignee: Bromine Compounds, Ltd.Inventors: Jakob Oren, Hugo Kesselman, Joshua Hermolin
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Patent number: 5185475Abstract: A method for preparing paracumylphenol in a highly selective manner which comprisesa. reacting alpha methylstyrene with a purity greater than about 99.5 wt. % with a molecular excess of phenol having a purity greater than about 99.95 wt. % in the contact presence of a solid organic cation exchange resin at a temperature of from about 40.degree. C. to about 100.degree. C. and obtaining a stream containing paracumylphenol, phenol and small quantitities of side reaction products comprising orthocumylphenol and alpha methylstyrene dimers,b. removing excess phenol and other unwanted materials which are lower boiling than paracumylphenol, thereby leaving a stream which is at least about 99 wt. % paracumylphenol.Type: GrantFiled: June 1, 1992Date of Patent: February 9, 1993Assignee: General Electric CompanyInventor: Gaylord M. Kissinger
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Patent number: 5124490Abstract: Acid contaminants leached from acidic ion-exchange resins and carried in process streams with phenol are separated from the phenol by passing the process stream in contact with an anionic exchange resin, whereby the acid contaminants react with and bond to the anionic exchange resin.Type: GrantFiled: June 17, 1991Date of Patent: June 23, 1992Assignee: General Electric CompanyInventor: Michael J. Cipullo
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Patent number: 5087768Abstract: A process for the purification of dihydroxybiphenyls, preferably 4,4'-dihydroxybiphenyl, by acylation of the preparation medium of the dihydroxybiphenyl and selective precipitation of the biphenyl diester (diacetylbiphenyl), followed by conversion of the biphenyl diester to dihydroxybiphenyl.Type: GrantFiled: October 1, 1990Date of Patent: February 11, 1992Assignee: Rhone-Poulenc ChimieInventor: Alain Nonn
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Patent number: 4992599Abstract: Crude phenol and also individual phenol fractions from tars or the hydrogenation of coal are purified from contaminating organic bases and sulfur compounds by treating the phenols with phthalic acid anhydride and optionally a quinone and distillation.Type: GrantFiled: December 13, 1989Date of Patent: February 12, 1991Assignee: Rutgerswerke AGInventors: Jorg Talbiersky, Bernhard Wefringhaus, Konrad Stolzenberg, Wolfgang Bergins
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Patent number: 4766254Abstract: Product losses and color formation are sometimes encountered in the synthesis of bisphenol A from phenol and acetone in the presence of a cation exchange resin, particularly in the crude product stream from which bisphenol A has been separated via its phenol adduct. Such losses are suppressed and the crude product stream stabilized and decolorized by contact with an anion exchange resin.Type: GrantFiled: October 5, 1987Date of Patent: August 23, 1988Assignee: General Electric CompanyInventors: Gary R. Faler, Michael J. Cipullo
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Patent number: 4740635Abstract: A process for crystallizing bisphenol-A which comprises:a. adding water to a mixture comprising bisphenol-A, about 0.5 to 15 weight percent of diphenol isomers and impurities, said mixture essentially free of phenol,b. maintaining the combined water and said mixture of (a) at a temperature sufficient to melt the solid material of step (a),c. adiabatically cooling the water and said mixture to below about 90.degree. C., andd. separating crystalline bisphenol-A from the mother liquor.Type: GrantFiled: October 20, 1986Date of Patent: April 26, 1988Assignee: General Electric CompanyInventors: Isabel M. Gomes de Matos, Gaylord M. Kissinger
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Patent number: 4740634Abstract: A process for crystallizing bisphenol-A which comprises:a. adding water to a mixture comprising bisphenol-A, about 0.5 to 15 weight percent of diphenol isomers and impurities, said mixture essentially free of phenol,b. maintaining the combined water and said mixture of (a) at a temperature sufficient to melt the solid material of step (a),c. adiabatically cooling the water and said mixture to below about 90.degree. C.,d. separating crystallized bisphenol-A from the mother liquor, ande. washing the crystallized bisphenol-A with an organic solvent which is at least substantially insoluble in water.Type: GrantFiled: October 20, 1986Date of Patent: April 26, 1988Assignee: General Electric CompanyInventors: Isabel M. Gomes de Matos, Gaylord M. Kissinger
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Patent number: 4720596Abstract: A process for removing phenol from water which comprises contacting a phenol bearing water stream with a bisphenol-A melt thereby separating phenol from the water.Type: GrantFiled: December 9, 1986Date of Patent: January 19, 1988Assignee: General Electric CompanyInventors: Gaylord M. Kissinger, Isabel M. Gomes de Matos
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Patent number: 4695410Abstract: The disclosed process is employed to recover phenol from aqueous solutions produced by distillation of the product of a process for producing a phenyl ester by the reaction of a carboxylic acid and phenol. Purified phenyl ester is employed to extract phenol from the aqueous solution. The extract is combined with raw product for recovery of the phenol and phenyl ester. In a preferred embodiment the process for producing the phenyl ester is continuous and the extract containing phenol and phenyl ester are fed to the dewatered ester stream for product recovery.Type: GrantFiled: August 29, 1986Date of Patent: September 22, 1987Assignee: Monsanto CompanyInventors: Gary J. Lynch, Chen-Hsyong Yang
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Patent number: 4533764Abstract: Occluded organic solvent is removed from bisphenol crystals by placing in water maintained at a temperature sufficient to form a molten water-bisphenol phase, holding at that temperature for a time sufficient to transfer the organic solvent to the water phase, flash distilling the organic solvent, cooling molten water-bisphenol phase to produce crystallization and thereafter recovering the bisphenol.Type: GrantFiled: March 29, 1984Date of Patent: August 6, 1985Assignee: The Dow Chemical CompanyInventors: Feng-Chih Chang, David E. Busby, Susan A. Wernl
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Patent number: 4529823Abstract: This invention is directed to a method of purifying crude bisphenol-A by crystallization with agitation in phenolic water having less than 30 weight percent phenol. The crystals obtained have a morphology similar to that of aqueous crystallized bisphenol-A with a significantly higher degree of purity than crystals obtained from an aqueous crystallization. The use of an organic solvent, foreign to the bisphenol-A synthesis reaction, for either washing or crystallization can be avoided and only small quantities of phenol and water are required when providing pure bisphenol-A for polycarbonate synthesis by this process.Type: GrantFiled: April 2, 1984Date of Patent: July 16, 1985Assignee: General Electric CompanyInventor: Ashok K. Mendiratta
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Patent number: 4469561Abstract: A method for simultaneously extracting and recovering 2,2-bis(4-hydroxy phenyl) propane and phenol from aqueous effluent streams by liquid-liquid extraction using toluene.Type: GrantFiled: January 17, 1983Date of Patent: September 4, 1984Assignee: General Electric CompanyInventors: Subhas K. Sikdar, Viney P. Aneja
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Patent number: 4092364Abstract: The process of preparing diphenyl oxide from caustically hydrolyzing chlorobenzene, wherein phenol is a by-product, is improved by recycling the phenol. The improvement not only maximizes the yield of diphenyl oxide while minimizing the yield of phenol, but it also increases the yield of desirable by-products, such as phenylphenols and biphenylylphenyl ethers.Type: GrantFiled: June 14, 1976Date of Patent: May 30, 1978Assignee: The Dow Chemical CompanyInventor: William E. Smith