Abstract: 2-Methyl-1-propanol is difficult to separate from 2-butanol by conventional distillation or rectification because of the proximity of their boiling points. 2-Methyl-1-propanol can be easily separated from 2-butanol by azeotropic distillation. Effective agents are sulfolane, acetonitrile and acetal.

Abstract: 2-Methyl-1-propanol is difficult to separate from 2-methyl-1-butanol by conventional distillation or rectification because of the proximity of their boiling points. 2-Methyl-1-propanol can be readily separated from 2-methyl-1-butanol by azeotropic distillation. Effective agents are tetrahydrofuran, methyl acetate and toluene.

Abstract: The present invention relates to a process for continuously preparing unsaturated carboxylic acid esters by esterifying an (aliphatic) alcohol having 1 to 8 carbon atoms with an unsaturated carboxylic acid in the presence of a cation exchange resin catalyst, characterized in that the process is conducted by continuously circulating said reactants in contact with said catalyst from the top to the bottom through a reactor which is composed in the form of a fixed bed divided into 1 to 10 steps wherein each step comprises a catalyst bed, a filter and a air inlet, and has a thermal insulating outer wall, supplying a vaporizing heat for extraction of water, which is produced during the reaction, through a heat exchanger outside the reactor, circulating the reactants between the reactor and the heat exchanger by means of a circulating pump, contacting an azeotropic mixture of water vaporized by the heat exchanger and an alcohol with an alcohol circulating in a column tower or a raw alcohol supplied from an alcohol i

Abstract: o-Xylene cannot be separated from p-xylene and m-xylene by conventional distillation or rectification because of the proximity of their boiling points. o-Xylene can be readily separated from mixtures of p-xylene and m-xylene by extractive distillation. Effective agents are o-cresol, dichloroacetic acid, methyl salicylate and 1-tetradecanol.

Abstract: 3-Carene and limonene cannot be separated from each other by rectification because of the closeness of their boiling points. They are readily separated by extractive distillation. Effective agents are: diethylene glycol phenyl ether, nonyl phenol, tripropylene glycol methyl ether, ethyl salicylate, 4-ethylphenol and 2-phenoxyethanol.

Abstract: 3-Carene and limonene cannot be separated from each other by rectification because of the closeness of their boiling points. They are readily separated by azeotropic distillation. Effective agents are: cyclopentanol, 2-nitropropane, ethyl formate amyl acetate dimethyl carbonate, tetrahydrofuran, acetic acid and 2-amino-amethyl-1-propanol.

Abstract: Butyraldehyde cannot be separated from ethanol by conventional distillation or rectification because they form a minimum boiling azeotrope. Butyraldehyde can be readily separated from ethanol by azeotropic distillation. Effective agents are ethyl formate, hexane and isopropyl ether.

Abstract: Vinyl aromatic monomer polymerization methods utilizing a composition of 2,6-di-tert-butyl-4-methylphenol and a substituted benzoquinonediimide compound are disclosed. Preferably, the composition is employed in an amount of 1 part to 10,000 parts per million parts monomer during distillation of styrene.

Abstract: Vinyl aromatic monomer polymerization methods utilizing a composition of 2,6-di-tert-butyl-4-methylphenol and a substituted benzoquinonediimide compound are disclosed. Preferably, the composition is employed in an amount of 1 part to 10,000 parts per million parts monomer during distillation of styrene.

Abstract: Isopropanol is difficult to separate from 2-butanone by conventional distillation or rectification because of the proximity of their boiling points. Isopropanol can be readily separated from 2-butanone by extractive distillation. Effective agents are o-cresol, ethylene glycol and nitroethane.

Abstract: o-Xylene cannot be separated from p-xylene and m-xylene by conventional distillation or rectification because of the proximity of their boiling points. o-Xylene can be readily separated from mixtures of p-xylene and m-xylene by azeotropic distillation. Effective agents are 3-methyl-1-butanol, methyl propionate and 3-pentanone.

Abstract: 1-Hexene is difficult to separate from hexane by conventional distillation or rectification because of the proximity of their boiling points. 1-Hexene can be readily separated from hexane by extractive distillation. Effective agents are hexyl acetate, methyl amyl alcohol and acetophenone.

Abstract: Benzene is difficult to separate from cyclohexane or cyclohexene by conventional distillation or rectification because of the close proximity of their boiling points. Benzene can be readily separated from cyclohexane or cyclohexene by using extractive distillation. Effective agents are: for benzene from cyclohexane, methyl acetoacetate; for benzene from cyclohexene, ethyl acetoacetate.

Abstract: p-Xylene cannot be separated from m-xylene by distillation or rectification because of the proximity of their boiling points. p-Xylene can be separated from m-xylene by means of extractive distillation. Effective agents are 3-ethylphenol and isopropyl palmitate. Effective agents for separating mixtures of p-xylene, m-xylene and o-xylene are 2-butoxyethyl acetate and 1,1,1-trichloroethane.

Abstract: Ethanol is impossible to separate from 2-butanone by conventional distillation or rectification because of the minimum boiling azeotrope between these two. Ethanol can be readily separated from 2-butanone by extractive distillation. Effective agents are dipromyl amine, phenol and dimethylsulfoxide.

Abstract: 3-Methyl-2-butanol, 2-pentanol and 1-butanol are difficult to separate by conventional distillation or rectification because of the proximity of their boiling points. Mixtures of these three can be readily separated from each other by azeotropic distillation. Effective agents are hexyl acetate, hexane and 3-methyl pentane.

Abstract: Ethanol is difficult to separate from isopropanol by conventional distillation or rectification because of the proximity of their boiling points. Ethanol can be readily separated from isopropanol by extractive distillation. Effective agents are dipentene, anisole and ethyl benzene.

Abstract: m-Xylene is very difficult to separate from mixtures of p-xylene and o-xylene by conventional distillation or rectification because of the proximity of their boiling points. m-Xylene can be readily separated from p-xylene and mixtures of p-xylene and o-xylene by azeotropic distillation. An effective agent is tetraethyl ortho silicate.

Abstract: Heptane is difficult to separate from 1-heptene by conventional distillation or rectification because of the proximity of their boiling points. Heptane can be readily separated from 1-heptene by extractive distillation. Effective agents are diacetone alcohol, ethyl butyrate and dimethylsulfoxide.

Abstract: p-Xylene cannot be separated from m-xylene by distillation or rectification because of the proximity of their boiling points. p-Xylene can be separated from m-xylene by means of extractive distillation. Effective agents are 3-ethylphenol and 1,1,2-trichloroethane. Effective agents for separating mixtures of p-xylene, m-xylene and o-xylene are 2-butoxyethyl acetate and 1,1,1-trichloroethane.

Abstract: 3-Methyl-2-butanol is difficult to separate from 2-pentanol by conventional distillation or rectification because of the proximity of their boiling points. 3-Methyl-2-butanol can be readily separated from 2-pentanol by azeotropic distillation. Effective agents are 2,2-dimethyl butane, ethyl acetate and dioxane.

Abstract: Ethanol is difficult to separate from isopropanol by conventional distillation or rectification because of the proximity of their boiling points. Ethanol can be readily separated from isopropanol by azeotropic distillation. Effective agents are sec. butyl acetate, hexene-1 and 1,3-dioxolane.

Abstract: Methylene chloride is difficult to separate from tetrahydrofuran by conventional distillation or rectification because of the proximity of their vapor pressures. Methylene chloride can be readily separated from tetrahydrofuran by extractive distillation. Effective agents are 1-pentanol, 1,2-butanediol and 3-nitrotoluene.

Abstract: A process for recovering column bottom residues produced by distillation of ethylene glycol resulting from an aromatic polyester production process, involving treating the residues with an aromatic mono-alkyl ester and distilling the reaction product.

Abstract: 2-Butanone is difficult to separate from isopropanol by conventional distillation or rectification because of the proximity of their boiling points. 2-Butanone can be readily separated from isopropanol by azeotropic distillation. Effective agents are 3-methyl pentane, methyl t-amyl ether and acetonitrile.

Abstract: Glycerine is difficult to separate from bis(hydroxymethyl)tetrahydrofuran by conventional distillation or rectification because of the proximity of their boiling points. Glycerine can be readily separated from bis(hydroxymethyl)tetrahydrofuran by azeotropic distillation. Effective agents are m-xylene, beta-pinene and dicyclopentadiene.

Abstract: Ethyl benzene is difficult to separate from xylenes by conventional distillation or rectification because of the proximity of their boiling points. Ethyl benzene can be readily separated from xylenes by azeotropic distillation. Effective agents for separating ethyl benzene from p-xylene are methyl formate, n-butanol and cyclopentanol; from p-xylene and m-xylene, n-butanol.

Abstract: 1-Butanol is difficult to semarate from 2-pentanol by conventional distillation or rectification because of the proximity of their boiling points. 1-Butanol can be readily separated from 2-pentanol by azeotropic distillation. Effective agents are 1-octene, hexane and methyl cyclohexane.

Abstract: 3-Methyl-2-butanol is difficult to separate from 2-pentanol by conventional distillation or rectification because of the proximity of their boiling points. 3-Methyl-2-butanol can be readily separated from 2-pentanol by extractive distillation. Effective agents are acetamide or 2,2,2-trichloroethanol.

Abstract: Ethanol is difficult to separate from isopropanol by conventional distillation or rectification because of the proximity of their boiling points. Ethanol can be readily separated from isopropanol by azeotropic distillation. Effective agents are acetonitrile and methylene chloride.

Abstract: 3-Methyl-2-butanol is difficult to separate from 1-butanol by conventional distillation or rectification because of the proximity of their boiling points. 3-Methyl-2-butanol can be readily separated from 1-butanol by azeotropic distillation. Effective agents are methyl acetoacetate and dioxane.

Abstract: 3-Methyl-2-butanol is difficult to separate from 1-butanol by conventional distillation or rectification because of the proximity of their boiling points. 3-Methyl-2-butanol can be readily separated from 1-butanol by extractive distillation. Effective agents are ethyl n-valerate, dimethylacetamide and dimethylsulfoxide.

Abstract: Benzene is difficult to separate from cyclohexane or cyclohexene by conventional distillation or rectification because of the close proximity of their boiling points. Benzene can be readily separated from cyclohexane or cyclohexene by using azeotropic distillation. Effective agents are: for benzene from cyclohexane, dimethoxymethane; for benzene from cyclohexene, methanol.

Abstract: 1-Decene is impossible to separate from 2-octanone by conventional distillation or rectification because the two compounds form a minimum boiling azeotrope. 1-Decene can be readily separated from 2-octanone by azeotropic distillation. Effective agents are 1-propanol, 2-ethoxyethanol, and methanol.

Abstract: 1-Decene is difficult to separate from 2-octanone by conventional distillation or rectification because of the proximity of their boiling points. 1-Decene can be readily separated from 2-octanone by azeotropic distillation. Effective agents are butyl propionate and 1-propanol.

Abstract: Benzene and other aromatics are separated from a stream of mixed hydrocarbons containing both aromatics and non-aromatics by extractive distillation with a solvent system containing dimethyl sulfoxide and optionally a co-solvent, preferably water, followed by distillation stripping of the aromatics from the enriched solvent system, and recycle of the lean solvent system to the extractive distillation step.

Abstract: Disclosed is a method for recovering carboxylic acids having from one to ten carbon atoms, and particularly formic acid, acetic acid and mixtures of formic and acetic acids, from aqueous solutions, in which the aqueous solution is contacted with solvent consisting essentially of mixed trialkylphosphine oxides in counter-current liquid-liquid extraction flow in a contacting step to thereby transfer the acids from the aqueous solution to the solvent, thus producing a raffinate relatively low in acid content and a rich solvent. The rich solvent is preferably dehydrated to separate water therefrom and yield a dehydrated rich solvent. The dehydrated rich solvent then has the acids stripped from it and the resulting lean solvent is then returned to the liquid-liquid extraction step, while the separated acids are split into their constituent components in a distillation operation.

Abstract: Hexane is difficult to separate from vinyl acetate and/or methyl acrylate by conventional distillation or rectification because of the closeness of their boiling points. Hexane can be readily separated from vinyl acetate and/or methyl acrylate by extractive distillation. Effective agents are dimethylsulfoxide and dimethylformamide.

Abstract: Separation of ethylene glycol and diethylene glycol from dimethyl terephthalate is accomplished by distillation using methyl benzoate or the methyl ester of p-toluic acid as an azeotropic agent.

Abstract: alpha-Phellandrene is difficult to separate from d-limonene by conventional distillation or rectification because of the proximity of their boiling points. alpha-Phellandrene can be readily separated from d-limonene by azeotropic distillation. Effective agents are n-butyl acetate and sulfolane.

Abstract: 1-Decene is difficult to separate from decane by conventional distillation or rectification because of the proximity of their boiling points. 1-Decene can be readily separated from decane by azeotropic distillation. Effective agents are methyl propionate, ethyl butyrate and methyl t-butyl ether.

Abstract: 1-Octene is difficult to separate from octane by conventional distillation or rectification because of the proximity of their boiling points. 1-Octene can be readily separated from octane by azeotropic distillation. Effective agents are ethyl formate, ethyl acetate and t-amyl methyl ether.

Abstract: alpha-Phellandrene is difficult to separate from 3-carene by conventional distillation or rectification because of the proximity of their boiling points. alpha-phellandrene can be readily separated from 3-carene by azeotropic distillation. Effective agents are methyl formate, nitroethane and acetal.

Abstract: 2-Butanol is difficult to separate from t-amyl alcohol by conventional distillation or rectification because of the proximity of their boiling points. 2-Butanol can be readily separated from t-amyl alcohol by extractive distillation. Effective agents are methyl caproate, adiponitrile and cyclopentanone.

Abstract: 1-Propanol is difficult to separate from 2-butanol by conventional distillation or rectification because of the proximity of their boiling points. 1-Propanol can be readily separated from 2-butanol by extractive distillation. Effective agents are isobutyl acetate, isobornyl methyl acetate and ethyl butyrate.

Abstract: Ethanol is difficult to separate from isopropanol by conventional distillation or rectification because of the proximity of their boiling points. Ethanol can be readily separated from isopropanol by extractive distillation. Effective agents are methyl caproate, cyclopentane and isobutyl acetate.

Abstract: 2-Butanol is difficult to separate from t-amyl alcohol by conventional distillation or rectification because of the proximity of their boiling points. 2-Butanol can be readily separated from t-amyl alcohol by azeotropic distillation. Effective agents are ethyl acetoacetate, nitroethane and 3-pentanone.

Abstract: Ethanol is difficult to separate from isopropanol by conventional distillation or rectification because of the proximity of their boiling points. Ethanol can be readily separated from isopropanol by azeotropic distillation. Effective agents are methyl ethyl ketone, cyclopentane and 2-pyrrolidinone.

Abstract: 1-Propanol is difficult to separate from 2-butanol by conventional distillation or rectification because of the proximity of their boiling points. 1-Propanol can be readily separated from 2-butanol by azeotropic distillation. Effective agents are t-butyl methyl ether, 1,4-dioxane and ethyl formate.

Abstract: For the separation of butenes and butanes by extractive distillation, a charge mainly containing butenes and butanes is contacted in an extractive distillation column under pressure with a first selective polar solvent, S1 (e.g., dimethyl formamide), the butanes being collected at the top. The solvent S1 containing the butenes and passing out at the bottom is mixed with a second solvent, S2, having a boiling point intermediate between that of butenes and that of the solvent S1, the mixture passing into a desorption column under pressure, where the butenes are collected at the top. The mixture of solvent S1 and S2 is separated in a purification column under atmospheric pressure, the solvent S2 passing out at the top is recycled to the desorption column, and the solvent S1 passing out at the bottom is recycled to the extractive distillation column.