- PREPARATION OF HIGH ASSAY DECABROMODIPHENYL OXIDE
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A process is described for producing a reaction-derived decabromodiphenyl oxide product of high purity. In a continuous bromination process, partially brominated diphenyl oxide and coproduct hydrogen bromide are formed by bringing together elemental bromine and diphenyl oxide continuously in a first reaction zone. The partially brominated diphenyl oxide formed has an average of about 2-6 bromine atoms per molecule. The vapor phase and the partially brominated diphenyl oxide are removed continuously from the first reaction zone as separate entities. Then, or after storage, partially brominated diphenyl oxide is fed to a second reaction zone. This zone contains a refluxing reaction mixture comprising (i) an excess of bromine and (ii) a catalytic quantity of Lewis acid bromination catalyst. As the reaction in this zone is taking place, hydrogen bromide coproduct is removed therefrom in a sufficient amount to form a reaction-derived decabromodiphenyl oxide product of high purity.
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Page/Page column 6-7
(2008/06/13)
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- PREPARATION OF DECABROMODIPHENYL OXIDE
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This invention provides a process for producing decabromodiphenyl oxide from a liquid mixture. The liquid mixture is derived from bromine, a Lewis acid catalyst, and a diphenyl oxide species selected from the group consisting of (i) diphenyl oxide,(ii) partially brominated diphenyl oxide,(iii) decabromodiphenyl oxide having about 0.5% or more nonabromodiphenyl oxide, and(iv) any combination of (i)-(iii). The process comprises distilling bromine and hydrogen bromide from the liquid mixture while feeding bromine to the liquid mixture.
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Page/Page column 4
(2008/06/13)
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- PREPARATION OF HIGH ASSAY DECABROMODIPHENYL OXIDE
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This invention provides a process of preparing reaction-derived decabromodiphenyl oxide product of high purity. The process comprises feeding a solution comprising a solvent and diphenyl oxide and/or partially brominated diphenyl oxide into a reaction zone containing a refluxing reaction mixture comprising an excess of bromine and a catalytic amount of Lewis acid bromination catalyst. Substantially concurrently with the feeding, a sufficient amount of hydrogen bromide coproduct is removed from the reaction zone so as to form a reaction-derived decabromodiphenyl oxide product of high purity.
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Page/Page column 4-5
(2008/06/13)
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- Process for higher purity decabromodiphenyl oxide
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A process for substantially perbrominating diphenyl ether comprising the steps of: (A) adding the diphenyl ether to a mixture of: (i) a greater than 400 percent excess of the stoichiometric amount of bromine; and (ii) a catalytically effective amount of a Lewis acid catalyst; (B) heating said mixture to an elevated temperature during the addition; and (C) continuing the reaction at an elevated temperature after addition of the aromatic compound has been completed.
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Page/Page column 3-4
(2008/06/13)
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- PREPARATION OF HIGH ASSAY DECABROMODIPHENYL OXIDE
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Process technology for producing very pure reaction-derived decabromodiphenyl oxide is described. Diphenyl oxide or partially brominated diphenyl oxide or a mixture of either or both of these is fed substantially continuously over a period of about 2 to about 12 hours into a reactor containing an excess of refluxing bromine containing Lewis acid bromination catalyst, and substantially concurrently reducing the content of hydrogen bromide present in the reactor whereby a decabromodiphenyl oxide product having a purity of over 99%, preferably 99.5% or more, is formed in the reactor.
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Page/Page column 12-13
(2008/06/13)
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- A PROCESS FOR PREPARING POLYBROMINATED COMPOUNDS
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A process for preparing a polybrominated product such as decabromodiphenyl ether and decabromodiphenyl ethane, which comprises brominating a reduced particle size precursor of said polybrominated product in an organic solvent or in bromine as a solvent, wherein the bromination is carried out either concurrently with or subsequent to said particle size reduction, forming the polybrominated product and separating the same from the reaction mixture.
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Page/Page column 16-20
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- PREPARATION OF DECAHALODIPHENYL OXIDE
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This invention provides a process of preparing reaction-derived decahalodiphenyl oxide of high purity. The process comprises cofeeding separate feeds of (a) diphenyl oxide and/or partially brominated diphenyl oxide and (b) bromine chloride, bromine chloride and bromine, or bromine chloride and chlorine to a refluxing reaction mixture comprising bromine and at least one Lewis acid bromination catalyst so that high purity decahalodiphenyl oxide is formed.
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Page/Page column 12
(2008/06/13)
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- Method of detecting decabromodiphenyl ether
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A method of detecting decabromodiphenyl ether, includes applying tetrahydrofuran to a sample, and then adding n-hexane thereto, drying the supernatant of the resultant, and subjecting the supernatant to infrared spectrometry.
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Page/Page column 2-3
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- PERBROMINATION OF BENZENE AND SOME OF ITS DERIVATIVES
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Perbrominated compounds - pentabromophenol, hexabromobenzene, pentabromotoluene, polychlorobromobenzenes, and decabromodiphenyl ether - have been obtained.Substitution bromination has been discovered in treating diphenyl sulfoxide, diphenyl sulfide, diphenylmethane, diphenyl oxide, and benzophenone with excess bromine in the presence of AlBr3.A series of ethers and esters of pentabromophenol have been obtained; their hydrolysis has been carried out.A negative influence of ferric halides has been discovered in exhaustive bromination of aromatic compounds.
- Golounin, A. V.,Shukhta, T. K.,Kirienko, E. K.,Petrova, M. P.,Esavkin, E. V.
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p. 1167 - 1169
(2007/10/02)
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- Process for producing purified brominated aromatic compounds
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A process for purifying crude brominated aromatic compounds such as decabromodiphenyl oxide containing impurities. The crude brominated aromatic compound undergoes a single processing step of grinding in the presence of heated air. The temperature is sufficient to effect substantial removal of impurities and yet remains below the melting point of the brominated aromatic compound.
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- Process for producing purified brominated aromatic compounds
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Highly purified brominated aromatic compounds such as decabromodiphenyl ether, pentabromophenol, and the like may be obtained by grinding the crude brominated product to provide particles predominantly less than about 20 microns in diameter and thereafter heating the crude ground brominated product for a time and at a temperature in order to effect substantial removal of the bromine and hydrogen bromide impurities therefrom. Optionally, the product may be ground a second time after the heating step to optimize product particle size and liberate residual impurities. The foregoing procedure is especially effective where the brominated compound is a thermally stable solid under the conditions of treatment and is substantially free from impurities containing aliphatic and alicyclic hydrocarbon groups.
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- Recovery of brominated biphenyl oxide
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A process for preparing polybrominated aromatic compounds which comprises (a) reacting an aromatic compound with bromine in the presence of a metal halide halogenation catalyst and solvent quantities of methylene bromide, and (b) adding a lower alkanol to the thereby produced reaction mixture to precipitate polybrominated aromatic product.
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- Process for the complete bromination of non-fused ring aromatic compounds
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There is disclosed a process for the preparation of completely brominated derivatives of aromatic compounds comprising one or more phenyl groups which may contain substituents, side chains or be partially-brominated. The complete bromination is effected by utilizing liquid bromine as a reaction solvent whereby the starting aromatic material is reacted with an excess of bromine which contains a bromination catalyst and the mixture is refluxed for a sufficient time. Use of these brominated derivatives as fire retarding agents is nylon and polyester is also disclosed.
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