Abstract: Separate isomers via supercritical gas extraction.

Abstract: A process for the separation of isomeric cresols includes the step of crystallizing from a medium containing phenolic and solvent components.

Abstract: A method of eliminating color-causing impurities in mixtures of aminoethylpiperazine, polyoxypropylenediamines and alkylphenols by treatment with N,N-diethylhydroxylamine is described. These alkylphenols such as nonylphenol are used in epoxy resins in the automotive and electronics industry. Discoloration of the phenol and subsequent resin occurs if the phenol is not treated with N,N-diethylhydroxylamine. Quantities on the order of 20 to 500 ppm are effective. The decolorization reaction may be conducted at a temperature in the range from about 25.degree. to 50.degree. C.

Abstract: A process is disclosed for separating 3,5-xylenol or 3,4-xylenol from other closely boiling polymethylated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with the xylenol over other related phenolics in the mixture. The preferentially-formed complex of the xylenol may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of the xylenol.

Abstract: A process is disclosed for separating nitrated phenolic compounds from other nitrated and unnitrated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with one of the phenolics over other related phenolics in the mixture. The preferentially-formed complex of one of the phenolics may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one phenolic. The process is particularly suitable for resolving a mixture comprising phenol or cresol from their ortho-nitrated derivatives, or a mixture of two isomeric nitrated phenols or cresols or a mixture of mono-and dinitrated phenols or cresols.

Abstract: A process is provided for recovering the crystallization medium used for separating a 2,6-disubstituted phenol (DSP) from a feedstock containing it and a phenol in which only one of the 2 or 6 carbon positions are substituted (MSP).

Abstract: A process is disclosed for reducing the concentration of o-ethylphenol in m,p-cresol by partially t-butylating a mixture of the above and equilibrating the resultant mixture to convert o-ethylphenol and its 6-t-butyl derivative to the thermodynamically most stable 4-t-butyl-o-ethylphenol. The resultant mixture may then be separated by fractional distillation to isolate m,p-cresol low in o-ethylphenol, optionally, the mono-t-butylated derivatives of m,p-cresol and leave behind the 4-t-butyl-o-ethylphenol, along with di-t-butylated derivatives of all the phenols.

Abstract: A process is disclosed for separating 5-isopropyl-m-cresol from other isopropylated m-cresols by treating a mixture of the isopropylated m-cresols with a metal halide salt. The metal halide salt preferentially forms a complex with 5-isopropyl-m-cresol over other related closely-boiling isopropylated m-cresols in the mixture. The preferentially-formed complex of 5-isopropyl-m-cresol may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, 5-isopropyl-m-cresol. The process is particularly suitable for isolating 5-isopropyl-m-cresol from closely-boiling isomers, and diisopropylated m-cresols.

Abstract: A process is disclosed for separating closely-boiling chlorinated phenolic compounds from other chlorinated and unchlorinated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with one of the phenolics over other related closely-boiling phenolics in the mixture. The preferentially-formed complex of one of the phenolics may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one phenolic. The process is particularly suitable for resolving a mixture comprising phenol or cresol from their closely-boiling ortho-chlorinated derivatives, or a mixture of two isomeric chlorinated phenols or cresols or a mixture of closely-boiling mono- and dichlorinated phenols or cresols.

Abstract: A process is disclosed for separating closely-boiling dihydric phenol compounds by treating a mixture of dihydric phenols with a metal halide salt. The metal halide salt preferentially forms a complex with one of the dihydric phenols over other related dihydric phenols in the mixture. The preferentially-formed complex of one of the dihydric phenols may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one dihydric phenol. The process is particularly suitable for resolving a mixture comprising hydroquinone and catechol, or a mixture of hydroquinone and resorcinol, or a mixture of homocatechol and hydroquinone, or a mixture of catechol and resorcinol.

Abstract: A process is disclosed for separating t-butylated phenolic compounds from other t-butylated and unbutylated phenolics by treating a mixture of the phenolics with a metal halide salt. The metal halide salt preferentially forms a complex with one of the phenolics over other related phenolics in the mixture. The preferentially-formed complex of one of the phenolics may then be isolated from the mixture and the complex decomposed to provide a product substantially enriched in, or substantially entirely composed of, one phenolic. The process is particularly suitable for resolving a mixture comprising phenol or cresol from their ortho-t-butylated derivatives, or a mixture of two isomeric t-butylated phenols or cresols or a mixture of mono- and di-t-butylated phenols or cresols.

Abstract: In removing a phenol from an aqueous solution containing the phenol, the phenol could be extracted quite effectively regardless of concentration of the phenol by using, as extracting solvent, a nitrogen-containing heterocyclic compound having a total carbon number of 9 or more either alone or in the state of a dilution with a water-insoluble organic solvent.

Abstract: A process for the separation of at least one cresol isomer from a feed mixture containing the cresol and xylenol which process employs a crystalline aluminosilicate adsorbent to selectively adsorb the cresol from the feed mixture. The process employs a desorbent material to recover the cresol. The process may employ a simulated moving bed flow scheme.

Abstract: A process for selective cracking of 1,4-disubstituted benzene compounds having at least one polar substituent. Mixtures containing isomers of such a compound are brought into contact with a specified type of shape selective crystalline zeolite catalyst under conditions of temperature and pressure conducive to reaction of said benzene compound, thereby selectively reacting the 1,4-disubstituted isomer in preference to the 1,2- and 1,3-disubstituted isomers of said polar benzene compound. The shape selective zeolite catalysts employed herein are crystalline zeolites characterized by a silica to alumina ratio of at least about 12 and a constraint index within the approximate range of 1 to 12.

Abstract: A feed containing a mixture of at least two alkylphenol isomers is contacted with a zeolite adsorbent to allow an alkylphenol isomer in the mixture to be selectively adsorbed on the adsorbent, and then the adsorbent is contacted with an aliphatic ketone desorbent to desorb the adsorbed isomer.

Abstract: A process for recovery of resorcinol from an aqueous resorcinol solution containing hydroquinone which comprises oxidizing an aqueous resorcinol solution containing about 10 to about 60% by weight of resorcinol and up to about 1% by weight of hydroquinone with molecular oxygen at conditions of pH 6.5 to 9.5, followed by recovering resorcinol from the resultant oxidation product.

Abstract: The components of cashew nut shell liquid have such similar physical characteristics that their separation into relatively pure components has been difficult and has prevented use of the oil in many technological areas. The reaction of certain components with bases prior to distillation enables increased separation efficiency.

Abstract: In a process for separating at least two alkyl phenols having close boiling points by azeotropic distillation of a mixture composed of the alkyl phenols with a hydrocarbon azeotroping agent, the improvement wherein said hydrocarbon azeotroping agent is selected from saturated aliphatic hydrocarbons of 9 to 13 carbon atoms having a boiling point of 150.degree. to 190.degree. C. at 760 mmHg.

Abstract: 4,4'-Dihydroxybiphenyl is produced by hydrolyzing 4,4'-dibromobiphenyl in the presence of a copper compound catalyst in an alkaline aqueous solution; extracting by-products from the alkaline aqueous solution with an alcohol or ketone which forms an organic phase; neutralizing or acidifying the alkaline aqueous solution with an acid; extracting the reaction product with the specific solvent; and crystallizing the reaction product from the extracted solution to obtain 4,4'-dihydroxybiphenyl having high purity.

Abstract: A improvement in the process for isolating and recovering meta- and para-cresols from crude cresol-containing compositions composed of cresol components, unreacted cymene components and high-boiling by-products, by distillation in a distillation zone, the characteristic features residing in that:(i) the unreacted cymene components content in the crude cresol-containing composition is adjusted to 5-25% by weight of said composition after the adjustment, and the water content of said composition is adjusted to become 0.17-1.

Abstract: A mixture of 2,4-/2,5-xylenol can be alkylated with a suitable alkylating agent over a strongly acidic divinylbenzene-styrene copolymer to afford a greater amount of 4-t-alkyl-2,5-xylenol than 6-t-alkyl-2,4-xylenol provided the alkylation is carried out at a suitably low temperature of 60.degree. C. or less.

Abstract: Effluent containing cresols such as are contained in Lurgi tar acids are separated by preferentially treating the cresols with an aqueous alkali metal carbonate or bicarbonate at elevated temperature for a time sufficient to form the alkali metal salt of at least part of the cresols, but not so long as to form any appreciable alkali metal salt of 2,6-xylenol or o-ethylphenol. The water soluble alkali metal salts of cresols are then separated from the water insoluble phenols and said salts acidified to "spring" the cresols and the water insoluble cresols separated from the aqueous solution.

Abstract: Para-cresol and meta-cresol are separated from a mixture of methylated and ethylated phenols by a two-stage process wherein the para-cresol is preferentially complexed with one or more anhydrous or dehydrated inorganic salts selected from calcium bromide, lithium bromide, manganese bromide and magnesium chloride. Then the meta-cresol is successively preferentially complexed with calcium bromide from the mixture of methylated and ethylated phenols from which the para-cresol complex has been removed. The anhydrous or dehydrated inorganic salt is added to the mixture of methylated and ethylated phenols including para-cresol and meta-cresol in an amount to give a mole ratio of the salt to para-cresol in the mixture in the range of about 0.5 to one to about 1.5 to one. The para-cresol-salt complex is removed from the mixture of methylated and ethylated phenols and then decomposed to recover the para-cresol.

Abstract: A process is disclosed for the stepwise separation of para-cresol and meta-cresol from a mixture of methylated and ethylated phenols. The para-cresol preferentially forms a complex with a dehydrated or anhydrous inorganic salt selected from the group consisting of calcium bromide, lithium bromide, manganese bromide and magnesium chloride. The meta-cresol isomer is separated from the mixture by formation of a complex with urea. Where the anhydrous or dehydrated inorganic salt is added firstly to the mixture of methylated and ethylated phenols including para-cresol and meta-cresol, the salt is provided in an amount to give a mole ratio of the salt to para-cresol in the mixture in the range of about 0.5 to one to about 1.5 to one. The para-cresol complexes with the salt and the complex is then removed from the mixture. The para-cresol-salt complex is thereafter decomposed to recover the para-cresol.

Abstract: Para-cresol is separated from a mixture comprising meta-cresol and various other methylated and ethylated phenols by preferentially complexing the para-cresol with one or more anhydrous or dehydrated inorganic salts selected from the group consisting of calcium bromide, lithium bromide, manganese bromide and magnesium chloride. The anhydrous inorganic salt is added to the phenolic mixture in an amount to give a mole ratio of salt to para-cresol in the mixture in the range of about 0.5 mole to one to about 1.5 mole to one. The para-cresol and salt form a complex and the complex is removed from the mixture of methylated and ethylated phenols. Then the complex is decomposed to recover the para-cresol and salt; the recovered salt may be recycled to complex with more para-cresol.

Abstract: A process is disclosed for the stepwise separation of para-cresol and meta-cresol from a mixture of methylated and ethylated phenols. The para-cresol forms a complex with a dehydrated or anhydrous inorganic halide salt selected from the group consisting of calcium bromide, lithium bromide, manganese bromide and magnesium chloride. The meta-cresol isomer is separated from the mixture by formation of a complex with sodium acetate. Where the anhydrous or dehydrated inorganic halide salt is added firstly to the mixture of methylated and ethylated phenols including para-cresol and meta-cresol, the halide salt is provided in an amount to give a mole ratio of the halide salt to para-cresol in the mixture in the range of about 0.5 to one to about 1.5 to one. The para-cresol complexes with the halide salt and the complex is then removed from the mixture. The para-cresol-salt complex is thereafter decomposed to recover the para-cresol.

Abstract: A mixture of 2,4-/2,5-xylenol can be alkylated with a suitable alkylating agent over a strongly acidic divinylbenzene-styrene copolymer to afford a greater amount of 4-t-alkyl-2,5-xylenol than 6-t-alkyl-2,4-xylenol provided the alkylation is carried out at a suitably low temperature of up to 60.degree. C.

Abstract: The relative amount of 2,5-xylenol in a 2,4-/2,5-xylenol mixture is significantly increased by passage of the xylenol mixture together with a suitable tertiary-alkylating agent through a reactor packed with a polymer-bound sulfonic acid catalyst at temperatures of 65.degree.-95.degree. C. and, preferably, 80.degree.-90.degree. C. The product stream from such a reactor under these conditions based on a 50:50 mixture of the two isomers contains a much greater amount of 6-t-alkyl-2,4-xylenol (t-alkylated 2,4-xylenol) than 4-t-alkyl-2,5-xylenol (t-alkylated 2,5-xylenol); consequently the resulting unalkylated 2,4-/2,5-xylenol mixture is greatly enriched in 2,5-xylenol. Recovery of the unalkylated mixture by fractionation thus affords a crude 2,5-xylenol which can be further purified to give pure 2,5-xylenol.

Abstract: A process for recovering phenols from a hydrocarbon mixture containing the same which comprises extracting such mixture with an aqueous formaldehyde solution.

Abstract: Highly effective chromatographic column packings are prepared by reacting hydroxyl groups on a silica surface with SiCl.sub.4 and then reacting the chlorosilylated surface with a polyglycol or polymeric glycol ester in a slurry reaction. Residual chlorosilane groups on the reacted surface are neutralized by reaction with methanol or other lower alkanol. The resulting modified silica has a bonded, essentially monomolecular organic surface film which provides thermal stability, uniform efficiency, and rapid analysis when the material is used as a column packing in gas-liquid chromatography.

Abstract: A method of purifying alkylphenyl from impurities contained therein resides in continuous crystallization of alkylphenol and continuous washing of the resulting crystals with a solvent.Washing of the crystals is performed in a layer formed by said crystals, the layer moving downward continuously, with a solvent moving upward.The invention makes it possible to purify alkylphenols effectively and produce them with a high degree of purity with minimum losses of the product, as well as to reduce consumption of the solvent.

Abstract: An inclusion compound comprising meta-cyclophane of the formula ##STR1## and at least one benzene derivative included therein. And a process for separating an isomer containing a substituent at least at the 1- and 4-positions from a mixture containing isomers of a benzene derivative, which comprises contacting the meta-cyclophane with the mixture containing isomers of a benzene derivative thereby to form an inclusion compound in which an isomer containing a substituent at least at the 1- and 4-positions is included in the meta-cyclophane, then separating the inclusion compound from the mixture, and thereafter separating the isomer from the inclusion compound.

Abstract: A process for improving the quality of diphenols by recrystallization from aqueous solvent systems.

Abstract: A process for improving the quality of diphenols by recrystallization from aqueous solvent systems.

Abstract: A process for the separation and purification of vinylphenol which comprises contacting crude vinylphenol containing vinylphenol and impurities such as phenol, alkylphenols, vinylphenol polymers and hydrocarbons countercurrently with an aqueous alkali solution together with a specific organic solvent.Vinylphenol obtained is useful as the raw material for the production of polyvinylphenol or a vinylphenol copolymer which is utilized as a thermoplastic resin, an ion exchange membrane, an adhesive, a glass fiber-reinforced composite or the like.