Abstract: Meta and para-diisopropylbenzenes cannot be easily separated from each other by distillation because of the closeness of their vapor pressures. m-Diisopropylbenzene can be readily removed from p-diisopropylbenzene by azeotropic distillation using certain ketones. Typical effective azeotropic distillation agents are acetophenone, 2-undecanone and acetonyl acetone.

Abstract: Formic acid cannot be completely removed from formic acid and water mixtures by distillation because of the presence of the maximum azeotrope. Formic acid can be readily removed from formic acid--water mixtures by extractive distillation in which extractive agent is a dicarboxylic acid mixed with certain high boiling organic compounds. Examples of effective agents are: itaconic acid and diethylene glycol diethyl ether; azelaic acid, heptanoic acid and 2-hydroxyacetophenone.

Abstract: Diastereomers can be separated with good industrial success with the aid of extractive distillation. The separation process is characterized in that an auxiliary which changes the partial pressure of the various diastereomers to be separated to a different degree and thus allows easier separation of the diastereomers by distillation is added during the distillation. Using the present process diastereomic cis/trans-permetric acid methyl esters and mixtures of menthol and isomenthol can be separated with isolation of 99% pure product.

Abstract: A process for producing a variety of chemical products, e.g., ethanol, by fermentation in which the product is removed from the fermentation medium as it is formed by liquid-liquid extraction using an extractant for the product which is immiscible with water. The extractant employed is chosen from the following groups: (A) double bond unsaturated aliphatic alcohols having 12 or more carbon atoms; (B) saturated branched chain aliphatic alcohols having 14 or more carbon atoms or mixtures thereof; (C) double bond unsaturated aliphatic acids having 12 or more carbon atoms; (D) aliphatic and aromatic mono-, di- or tri-esters having 12 or more carbon atoms, other than dibutyl phthalate; (E) aliphatic noncyclic ketones and aliphatic aldehydes having 12 or more carbon atoms; and (F) mixtures of extractants from groups (A) to (E) above or mixtures of at least one of the above extractants and at least one other extractant.

Abstract: 2-Pentanone cannot be completely removed from 2-pentanone and formic acid mixtures by distillation because of the presence of the maximum azeotrope. 2-Pentanone can be readily removed from 2-pentanone-formic acid mixtures by extractive distillation in which the extractive agent is a ketone, either alone or mixed with certain high boiling organic compounds. Examples of effective agents are cyclohexanone; diisobutyl ketone and octanoic acid; isophorone, hexanoic acid and butyl ether.

Abstract: Meta and para-diisopropylbenzenes cannot be easily separated from each other by distillation because of the closeness of their vapor pressures. m-Diisopropylbenzene can be readily removed from p-diisopropylbenzene by azeotropic distillation using certain nitrogenous compounds. Typical effective azeotropic distillation agents are ethanolamine and benzonitrile.

Abstract: 3-Methyl-2-butanone cannot be removed from 3-methyl-2-butanone and formic acid mixtures by distillation because of the presence of the maximum azeotrope between 3-methyl-2-butanone and formic acid. 3-Methyl-2-butanone can be readily removed from 3-methyl-2-butanone - formic acid mixtures by extractive distillation in which the extractive agent is dimethylacetamide, dimethylformamide or these with certain high boiling organic compounds.

Abstract: Meta- and para-diisopropylbenzenes cannot be easily separated from each other by distillation because of the closeness of their vapor pressures. m-Diisopropylbenzene can be readily removed from p-diispropylbenzene by azeotropic distillation using acetophenone. The acetophenone - m-diisopropylbenzene azeotrope can be separated by solvent extraction with propylene glycol to remove the acetophenone and the propylene glycol - acetophenone mixture is readily separated from each other by rectification.

Abstract: Dioxane cannot be completely removed from dioxane and formic acid mixtures by distillation because of the presence of the maximum azeotrope. Dioxane can be readily removed from dioxane - formic acid mixtures by extractive distillation in which the extractive agent is dimethylsulfoxide, either alone or admixed with certain high boiling organic compounds. Examples of effective agents are dimethylsulfoxide; DMSO and octanoic acid; DMSO, neodecanoic acid and methyl salicylate.

Abstract: Dioxane cannot be completely removed from dioxane and acetic acid mixtures by distillation because of the presence of the maximum azeotrope. Dioxane can be readily removed from dioxane - acetic acid mixtures by extractive distillation in which the extractive agent is N,N-dimethylacetamide or dimethylformamide, either alone or mixed with certain high boiling organic compounds. Examples of effective agents are N,N-dimethylacetamide; dimethylformamide and heptanoic acid; N,N-dimethylacetamide, heptanoic acid and diethylene glycol diethyl ether.

Abstract: Dioxane cannot be completely removed from dioxane and acetic acid mixtures by distillation because of the presence of the maximum azeotrope. Dioxane can be readily removed from dioxane-acetic acid mixtures by extractive distillation in which the extractive agent is dimethylsulfoxide, either alone or mixed with certain high boiling organic compounds. Examples of effective agents are dimethylsulfoxide; DMSO and octanoic acid; DMSO, hexanoic acid and isophorone.

Abstract: 2-Pentanone cannot be completely removed from 2-pentanone and formic acid mixtures by distillation because of the presence of the maximum azeotrope. 2-Pentanone can be readily removed from 2-pentanone formic acid mixtures by extractive distillation in which the extractive agent is dimethylsulfoxide, either alone or mixed with certain high boiling organic compounds. Examples of effective agents are dimethylsulfoxide; DMSO and octanoic acid; DMSO, hexanoic acid and isophorone.

Abstract: Formic acid cannot be completely removed from formic acid and water mixtures by distillation because of the presence of the maximum azeotrope. Formic acid can be readily removed from formic acid - water mixtures by extractive distillation in which the extractive agent is ethylene carbonate or propylene carbonate, either alone or mixed with certain high boiling organic compounds. Examples of effective agents are ethylene carbonate and heptanoic acid; propylene carbonate, benzoic acid and isophorone; propylene carbonate, heptanoic acid and 2-hydroxyacetophenone.

Abstract: A process of isolating dihydroxyacetone which is a useful intermediate in organic chemistry as well as being a sun-tanning agent. The process comprises passing a reaction mixture containing dihydroxyacetone in an organic solvent through at least one thin film evaporator to distil dihydroxyacetone separately from the solvent.

Abstract: The process for the acid-catalyzed reaction of acetone with methanol to form 2,2-dimethoxypropane may be significantly improved if a stoichiometric ratio of methanol/acetone is employed in the initial reaction.Of particular advantage is the use of stoichiometric amounts of reactants in order to (1) avoid the expense of using an excess of either reactant, and (2) facilitate the removal of the 2,2-dimethoxypropane as an azeotrope with the methanol, thereby avoiding costly and complex product recovery methods.

Abstract: Impure formic acid cannot be completely removed from formic acid-water-impurity mixtures by distillation because of the presence of the maximum azeotrope between formic acid and water. Formic acid can be readily removed from mixtures containing it, water and impurities of the ether, ester, ketone or diketone type by using extractive distillation in which the extractive agent is a higher boiling oxygenated, nitrogenous or sulfur containing organic compound or a mixture of these. Examples of effective agents are adiponitrile; sulfolane and salicyclic acid; dimethylformamide, N,N-dimethylacetamide and ethylene glycol ethyl ether acetate.

Abstract: Acetic acid cannot be easily removed from acetic acid--water mixtures by distillation because of the closeness of their boiling points and the deviation from ideal solution behavior. Acetic acid can be readily removed from mixtures containing it and water by using extractive distillation in which the extractive distillation agent is a mono carboxylic acid, either singly or admixed with high boiling organic compounds. Typical examples of effective agents are pelargonic acid; heptanoic acid and isophorone; neodecanoic acid, acetophenone and nitrobenzene.

Abstract: A process for extracting pure components from a multi-component system, said system comprising a mixture of at least two solids or liquids in a supercritical fluid at constant pressure, which involves making use of the cross-over pressure points of the components which comprise the system.

Abstract: Formic acid cannot be easily removed from acetic acid by distillation because of the closeness of their vapor pressures. Formic acid can be readily removed from acetic acid by extraction distillation. Typical extractive distillation agents are carboxylic acids in the range of hexamoic acid to neodecanoic acid with or without solvents such as methyl benzoate, acetophenone and nitrobenzene.

Abstract: Methyl t-butyl ether cannot be separated from close boiling hydrocarbons by distillation because of the proximity of their boiling points. Methyl t-butyl ether can be readily separated from close boiling hydrocarbons by using extractive distillation in which the extractive agent is higher boiling oxygenated, nitrogenous and/or sulfur containing organic compound or a mixture of two or more of these. Typical examples of effective agents are dimethylsulfoxide; dimethylsulfoxide and 2-octanone; dimethylsulfoxide, dimethylformamide and N-methyl pyrrolidone.

Abstract: Formic acid cannot be completely removed from formic acid - water mixtures by distillation because of the presence of the maximum azeotrope. Formic acid can be readily removed from mixtures containing it and water by using extractive distillation in which the extractive distillation agent is a sulfone. Typical examples of effective agents are thiophan sulfone; dimethyl sulfone and adiponitrile; phenyl sulfone, adiponitrile and acetophenone.

Abstract: Water cannot be completely removed from ethanol by distillation because of the presence of the minimum azeotrope. Ethanol can be readily dehydrated by using extractive distillation in which the water is removed as overhead product and the ethanol and extractive agent as bottoms and subsequently separated by conventional rectification. Typical examples of suitable extractive agents are methyl benzoate; trimellitic anhydride and methyl benzoate; dipropylene glycol dibenzoate, ethyl salicylate and resorcinol.

Abstract: Acetone cannot be completely removed from acetone-methanol mixtures by distillation because of the presence of the minimum boiling azeotrope. Acetone can be readily separated from methanol by using extractive distillation in which the extractive agent is dimethylformamide, either alone or admixed with other compounds. Typical examples of effective agents are: dimethylformamide; dimethylformamide and diethylene glycol; dimethyl formamide, glycerine and propylene glycol.

Abstract: In a hydroformylation process wherein an alpha-alkene of 2 to about 10 carbon atoms is reacted with carbon monoxide and hydrogen in the presence of a rhodium triorganophosphine complex to produce an aldehyde having one carbon atom more than the alkene, the aldehyde product being continuously separated from the liquid reaction medium by gas stripping or distillation, rhodium moiety is recovered from the condensed reactor overhead vapors by redistillation under defined conditions.

Abstract: A method of removing alicyclic ketones and chlorotrimethylphenol from a mixture of alicyclic ketones, chlorotrimethylphenol and trimethylphenol by azeotropically distilling such a mixture in the presence of a glycol or a dialkyl sulfoxide.

Abstract: Acetone cannot be completely removed from acetone-methanol mixtures by distillation because of the presence of the minimum boiling azeotrope. Acetone can be readily separated from methanol by using extractive distillation in which the extractive agent is a higher boiling oxygenated, nitrogenous and/or sulfur-containing organic compound or a mixture of two or more of these. Typical examples of effective agents are: Glycerine, 1,5-Pentanediol, Dimethylsulfoxide, n-Hexanol, Dioctyl phthalate and N,N-Dimethylacetamide.

Abstract: A process for stabilizing a silicon-containing methacrylate having the formula (I): ##STR1## wherein X is Si(OCH.sub.3).sub.3, Si(OCH.sub.3).sub.2 CH.sub.3, Si(OCH.sub.3)(CH.sub.3).sub.2 or Si(CH.sub.3).sub.3 which comprises adding 2,5-di-t-butylbenzoquinone to the silicon-containing methacrylate, whereby polymerization of the silicon-containing methacrylate can be inhibited. As a result, the silicon-containing methacrylate can be stabilized without any trouble in distillation step.

Abstract: An improved method of stripping unreacted alkylene glycol monoalkyl ethers and unreacted monocarboxylic or halogenated monocarboxylic acids from a mixture containing the monocarboxylic acid ester prepared therefrom by acid catalyzed esterification without any significant loss of the product ester. The method involves the injection of water into the distillate during the stripping and is particularly suitable for the recovery of propylene glycol monomethyl ether and acetic acid from esterification reaction mixtures containing a predominate amount of product propylene glycol monomethyl ether acetate. The process allows for removal and recovery or recycle of the ether and acid and the preparation of a higher purity product ester.

Abstract: Benzene is virtually impossible to separate from similar close boiling non-aromatic hydrocarbons by conventional rectification or distillation. Benzene can be readily separated from similar boiling non-aromatic hydrocarbons by using extractive distillation in which the extractive agent is a mixture of benzoic acid, maleic anhydride and/or phthalic anhydride plus a suitable solvent. A typical mixture comprises phthalic anhydride, maleic anhydride and adiponitrile.

Abstract: Methanol cannot be completely removed from its mixture with acetone by distillation because of the presence of the minimum binary azeotrope. Methanol can be readily removed from mixtures containing it and acetone by using extractive distillation to bring off the methanol as overhead product in a rectification column by using extractive distillation in which the extractive distillation agent is an effective higher boiling organic compound or a mixture of these. Typical examples of effective agents are acetophenone, 3-pentanone, 2,4-pentanedione, ethylacetoacetate, 2-butanone plus benzil.

Abstract: m-Xylene is difficult to separate from o-xylene by conventional rectification or distillation because of the close proximity of their boiling points. m-Xylene can be readily separated from o-xylene by using extractive distillation in which the extractive agent is ethyl-2-hydroxybenzoate; propoxypropanol puls 1,4-butanediol; sulfolane plus dimethylsulfoxide plus ethyl benzoate.

Abstract: The present invention provides an improvement in methods for preparing and processing readily polymerizable acrylate monomers. The improvement comprises employing phenyl-para-benzoquinone, 2,5-di-phenyl-para-benzoquinone, and mixtures thereof as process inhibitors. The process inhibitors are present in a concentration of about 50 to 3000 ppm, preferably about 250 to 2000 ppm, and most preferably about 500 ppm.

Abstract: A method for separating ethyl acetate from methyl ethyl ketone is described including distilling in an anhydrous condition a mixture of ethyl acetate-methyl ethyl ketone in a plate column in the presence of an effective amount of an organic extractive solvent which has the following properties: (1) is soluble in a boiling ethyl acetate-methyl ethyl ketone mixture; (2) does not form an azeotrope with ethyl acetate or methyl ethyl ketone; (3) boils higher than ethyl acetate and methyl ethyl ketone and (4) in combination with the ethyl acetate-methyl ethyl ketone mixture, results in a relative volatility of ethyl acetate to methyl ethyl ketone greater than 1.20.

Abstract: Isopropyl ether cannot be completely removed from isopropyl ether - methyl ethyl ketone mixtures by distillation because of the presence of the minimum binary azeotrope. Isopropyl ether can be readily removed from mixtures containing it and methyl ethyl ketone by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated, nitrogenous and/or sulfur containing organic compound or a mixture of these. Typical examples of effective agents are sulfolane; ethylene carbonate plus dimethylsulfoxide; adiponitrile plus dimethylformamide plus glycerine.

Abstract: Ethanol is concentrated from ethanol-water mixtures by extraction or extractive distillation with a solvent which is a cyclic ketone of at least seven carbons or cyclic alcohol of at least eight carbons such a cyclohexylcyclohexanone or cyclohexylcyclohexanol. In the extractive distillation process, a first overheads is produced which can be made to be steam with minimal ethanol content and a second overhead is produced which can be made to be essentially pure ethanol. The preferred solvents are also non-toxic, such that the alcohol can be used for human consumption.

Abstract: There is disclosed an improved process for the preparation of monochloroacetone by reacting acetone and chlorine in a vapor-liquid phase reactor and passing the reactor effluent through a fractionator to remove the liquid phase consisting mainly of monochloroacetone (MCA). The fractionator vapor phase effluent is consisting of acetone, hydrogen chloride, some monochloroacetone, and some reaction by-products sequentially fractionated in a series of condensers of varying temperatures such that the hydrogen chloride is isolated free of impurities and the remaining reaction materials, consisting mainly of acetone with some dissolved hydrogen chloride are available for recycling back into the reactor. The hydrogen chloride, isolated in the vapor phase, may be quenched with water to produce concentrated aqueous hydrochloric acid which may be used in other chemical procedures or it may be compressed into anhydrous hydrogen chloride.

Abstract: A process for the separation of a dissolved solid from an aqueous solution containing it, comprising the steps of (a) adding thereto an organic liquid which is a poor solvent for the dissolved solid and which forms an azeotrope with water, (b) subjecting the mixture to azeotropic distillation to separate at least a major portion of the water, (c) cooling the mixture thereby causing substantially complete separation of the dissolved solids, and (d) separating same from the mother liquor.

Abstract: A method for simultaneously extracting and recovering 2,2-bis(4-hydroxyphenyl) propane and phenol from aqueous effluent streams by liquid-liquid extraction using methyl isobutyl ketone.

Abstract: Toluene is virtually impossible to separate from similar boiling non-aromatic hydrocarbons by conventional rectification or distillation. Toluene can be readily separated from similar boiling non-aromatic hydrocarbons by using extractive distillation in which the extractive agent is a mixture of phthalic anhydride and/or maleic anhydride plus a suitable solvent. A typical mixture comprises phthalic anhydride, maleic anhydride and glycerol triacetate.

Abstract: The invention involves a process for substantially separating the components of mixtures of substances at least one of which is of low volatility while the other is of low or no volatility, the process using a compressed gas under supercritical conditions and an entrainer which increases the concentration of said mixture in the gaseous phase as well as the separation factor between the components to be separated. The process operates in two distillation zones the first of which substantially separates the components of low volatility in a process similar to a rectification process while the second distillation zone separates the top product of the first distillation zone from the gas with the aid of the entrainer which is condensed partially and in this state is passed in countercurrent to the gas carrying the separated component of low volatility.

Abstract: This invention relates to a process for working up the distillation residue obtained in the commercial production of tolylene diisocyanate by grinding, optionally accompanied and/or followed by chemical modification reactions. The finely divided powder obtained may be used as a reactive filler in the production of a variety of plastics.

Abstract: A process for isolating butadiene, with the aid of a selective solvent, from a C.sub.4 -hydrocarbon mixture which contains butadiene and small amounts of styrene and may contain oxygen, hydrocarbons more soluble than butadiene in the selective solvent and hydrocarbons less soluble than butadiene in the selective solvent, in which process the C.sub.4 -hydrocarbon mixture is separated by extractive distillation into a distillate which contains the less soluble hydrocarbons, a stream of butadiene and a stream containing the more soluble hydrocarbons, and in which a mixture of styrene and C.sub.4 -hydrocarbons is removed from the C.sub.4 -hydrocarbon mixture in a distillation zone upstream of the extractive distillation, the top product of the said distillation zone being fed to the extractive distillation.

Abstract: Process for changing the volatile aluminum chloride complex contained in an ethylbenzene production stream into a non-volatile, aluminum chloride product of a nature such that the ethylbenzene in the stream can be separated from the aluminum chloride catalyst by flash distillation. Conversion of the volatile aluminum chloride complex to a non-volatile aluminum chloride product is accomplished by adding selected alcohols, aldehydes, or ketones to the ethylbenzene stream.

Abstract: A process of recovering an n-hexane product which is free from aromatic compounds by extractive distillation from a mixture of aromatic and non-aromatic compounds. The mixture is fed to and distilled in a first distillation column, from which a benzene-containing sump product and the overhead product consisting of non-aromatic compounds are withdrawn. The distillate is laterally withdrawn above the feeding point of the feed mixture and transferred to the upper portion of a second distillation column. The hexane cut is withdrawn as sump product from the second distillation column and fed to an extractive distillation column approximately in the middle thereof and is extracted in the extractive distillation column with a selective solvent which is fed above the feeding point of the hexane cut consisting of the sump product of the second distillation column. The sump product containing the selective solvent is withdrawn from the extractive distillation column and the overhead thereof vapors are condensed.

Abstract: A process in which a mixture including phenol, cyclohexanone and cyclohexanol is fed to a point intermediate the top and bottom of a distillation column, an overhead stream comprising cyclohexanone and cyclohexanol is withdrawn from a point adjacent the top of the column and a bottoms stream comprising phenol is withdrawn from adjacent the bottom of the column. By feeding additional cyclohexanone to a point below where the mixture is fed, the cyclohexanone content of the bottoms is reduced. The process is useful in separating chemicals used in producing cyclohexanone from phenol for manufacturing caprolactam, a polyamide monomer, or for other purposes.

Abstract: Acetone produced as a by-product in the reaction of methyl acetate with carbon monoxide and hydrogen in the presence of a Group VIII noble metal catalyst and methyl iodide is recovered from the reaction mixture by supplying acetone to provide an acetone to methyl iodide molar ratio of at least 1:10 and distilling the mixture comprising methyl iodide, acetone and methyl acetate to separate substantially all of the methyl iodide and the supplied acetone and some of the methyl acetate from the remaining acetone and methyl acetate and thereafter separating the acetone from the methyl acetate.

Abstract: A method of inhibiting the polymerization of styrene which comprises mixing with the styrene a minor but effective quantity of an inhibitor compound selected from the group consisting of 2-methylbenzoquinone-4-oxime, 2,3,5-trimethylbenzoquinone-4-oxime and mixtures thereof.

Abstract: An extractive distillation process for separating one or more members of the group consisting of alkanols, alkanones, cycloalkanols and/or cycloalkanones from mixtures with phenol and/or cresol. One or more members of the group consisting of alkylated or unmodified cycloalkyl or aryl-derivatives of cyclohexanone or cyclohexanol having up to about 22 carbon atoms are employed as extractive solvent.

Abstract: A method for purifying benzotriazole, tolyl-triazole or mixtures of the two is disclosed. The method includes the steps of vacuum distillation of crude triazole and collection of the condensate. The crude triazole contains color bodies, diazotizable impurities which are color body precursors, or both. The color of the distilled triazole is improved by adding to the crude triazole, prior to vacuum distillation, an amount of formaldehyde sufficient for reaction with an appreciable proportion of the color bodies, the color body precursors, or both.

Abstract: A method for reducing losses due to reactions between hydrogen halides and olefinically unsaturated organic compounds in the presence of transition metals which act as catalysts for hydrohalogenation in mixtures containing same by adding to said mixtures a compound selected from the class consisting of alkyl diketones. The present invention is of particular value in the separation of components of said mixtures by distillation, but may also be usefully employed in any operation in which these mixtures are maintained in the presence of said catalytic materials. The present method offers advantages over the prior art because of the relative low toxicity and flammability of diketones and the fact that no undesirable solids are formed to foul process equipment as with some known methods.