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: Ethanol and t-butanol cannot be separated from each other by distillation because of the proximity of their boiling points. Ethanol can be readily separated from t-butanol by using extractive distillation in which the extractive agent is a higher boiling oxygenated organic compound or a mixture of two or more of these. Typical examples of effective agents are: methyl benzoate; benzyl benzoate and benzoic acid; methyl salicylate, hexahydrophthalic anhydride and salicylic acid.

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: Isobutyl acetate cannot be completely removed from isobutyl acetate - isobutanol - water mixtures by distillation because of the presence of the minimum ternary axeotrope. Isobutyl acetate can be readily removed from mixtures containing it, isobutanol and water 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 dimethylsulfoxide; dimethylsulfoxide and dimethylformamide; dimethylsulfoxide, dimethylformamide and N,N-dimethylacetamide.

Abstract: Isopropanol cannot be completely removed from isopropanol-isopropyl acetate-water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropanol can be readily removed from mixtures containing it, isopropyl acetate and water by using extractive distillation in which the extractive agent is a higher boiling ester of phthalic acid. Typical examples of effective agents are diisooctyl phthalate and methyl benzoate, dibutyl phthalate, methyl benzoate and nitromethane.

Abstract: 2-Butyl acetate cannot be completely removed from 2-butyl acetate-2-butanol-water mixtures by distillation because of the presence of the minimum ternary azeotrope. 2-butyl acetate can be readily removed from mixtures containing it, 2-butanol and water 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 N,N-dimethylacetamide; dimethylformamide and ethylene glycol; acetamide, dimethylsulfoxide and ethylene glycol.

Abstract: Isopropanol cannot be completely removed from isopropanol--isopropyl acetate--water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropanol can be readily removed from mixtures containing it, isopropyl acetate and water by using extractive distillation in which the extractive agent is a higher boiling benzoate mixed with certain oxygenated or nitrogeneous organic compounds. Typical examples are butyl benzoate and ethylene carbonate; methyl benzoate, 2-nitropropane and n-decanol.

Abstract: n-Propanol and 2-butanol cannot be separated from each other by distillation because of the proximity of their boiling points. n-Propanol can be readily separated from 2-butanol using extractive distillation in which the extractive agent is a higher boiling oxygenated organic compound or a mixture of two or more of these. Typical examples of effective agents are: methyl benzoate; benzoic acid and methyl benzoate; cinnamic acid, phthalic anhydride and methyl benzoate.

Abstract: Isopropanol and t-butanol cannot be separated from each other by distillation because of the proximity of their boiling points. Isopropanol can be readily separated from t-butanol by using extractive distillation in which the extractive agent is a higher boiling oxygenated organic compound or a mixture of two or more of these. Typical examples of effective agents are: methyl benzoate; methyl benzoate and hexahydrophthalic anhydride; phthalic anhydride, hexahydrophthalic anhydride and methyl benzoate.

Abstract: Ethanol and isopropanol cannot be separated from each other by distillation because of the proximity of their boiling points. Ethanol can be readily separated from isopropanol by using extractive distillation in which the extractive agent is a higher boiling oxygenated organic compound or a mixture of two or more of these. Typical examples of effective agents are: methyl salicylate; salicylic acid and hexahydrophthalic anhydride; salicylic acid, hexahydrophthalic anhydride and methyl benzoate.

Abstract: A continuous process and apparatus for drying aqueous solids by evaporation using a fluidizing oil and a surfactant wherein the fluidizing oil and surfactant are recovered and recycled separately or together. The aqueous solids may, or may not, have a heavy, natural oil associated with them.

Abstract: Isopropyl acetate cannot be completely removed from isopropyl acetate - isopropanol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropyl acetate can be readily removed for mixtures containing it, isopropanol and water by using extractive distillation in which the extractive agent is higher boiling oxygenated or nitrogenous organic compound or a mixture of these. Typical examples of effective agents are dimethylformamide; dimethylformamide and triethanolamine; N,N-dimethylacetamide and N-methyl pyrrolidone.

Abstract: n-Hexyl acetate cannot be completely removed from n-hexyl acetate- n-hexyl alcohol- water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Hexyl acetate can be readily removed from mixtures containing it, n-hexyl alcohol and water by using extractive distillation in which the extractive distillation agent is dimethylsulfoxide or a mixture of DMSO with a higher boiling organic compound. Typical examples of effective agents are DMSO; DMSO and tetraethylene glycol; DMSO, dimethylformamide and hexylene glycol.

Abstract: t-Amyl alcohol and isobutanol cannot be separated from each other by distillation because of the proximity of their boiling points. t-Amyl alcohol can be readily separated from isobutanol by using extractive distillation in which the extractive agent is a higher boiling organic compound or a mixture of two or more of these. Typical examples of effective agents are: dimethylformamide; N,N-dimethylacetamide; N,N-dimethylacetamide and dimethylsulfoxide; dimethylformamide, N,N-dimethylacetamide and phthalic anhydride.

Abstract: t-Amyl alcohol and isobutanol cannot be separated from each other by distillation because of the proximity of their boiling points. t-Amyl alcohol can be readily separated form isobutanol by using extractive distillation in which the extractive agent is a higher boiling organic compound or a mixture of two or more of these. Typical examples of effective agents are: dimethylsulfoxide; dimethylsulfoxide and N,N-dimethylacetamide; dimethylsulfoxide, dimethylformamide and phthalic anhydride.

Abstract: Isopropyl acetate cannot be completely removed from isopropyl acetate - isopropanol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropyl acetate can be readily removed from mixtures containing it, isopropanol and water by using extractive distillation in which the extractive agent is a higher boiling oxygenated or nitrogenous organic compound or a mixture of these. Typical examples of effective agents are diethanolamine; ethanolamine and N-methyl pyrrolidone; triethanolamine and N-methyl pyrrolidone.

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: n-Propyl acetate cannot be completely removed from n-propyl acetate - n-propanol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Propyl acetate can be readily removed from mixtures containing it, n-propanol and water by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated or nitrogenous organic compound or a mixture of these. Typical examples of effective agents are N-methylpyrrolidone; triethanolamine; N-methylpyrrolidone and ethylene glycol.

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 dimethylformamide; dimethylformamide and 1,4-butanediol; dimethylformamide, adiponitrile and dihexyl phthalate.

Abstract: Isopropanol cannot be completely removed from isopropanol-isopropyl acetate-water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropanol can be readily removed from mixtures containing it, isopropyl acetate and water by using extractive distillation in which the extractive agent is a higher boiling ester of phthalic acid. Typical examples of effective agents are diethyl phthalate, diisooctyl phthalate and methyl benzoate, dibutyl phthalate, methyl benzoate and nitromethane.

Abstract: n-Hexyl alcohol cannot be completely removed from n-hexyl acetate- n-hexyl alcohol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Hexyl alcohol can be readily removed from mixtures containing it, n-hexyl acetate and water by using extractive distillation in which the extractive distillation agent is a benzoate or a mixture of benzoates with higher boiling organic compounds. Typical examples of effective agents are benzyl benzoate; methyl benzoate and adiponitrile; ethyl benzoate, benzyl benzoate and methyl salicylate.

Abstract: m-Xylene is difficult to separate from o-xylene by conventional distillation or rectification 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 a mixture polychloro aromatic compounds. Typical examples of effective agents are 2,3,4,6-tetrachlorophenol and p-dichlorobenzene; dimethyltetrachloroterephthalate, 2,3,4,6-tetrachlorophenol and 1,2,4,5-tetrachlorobenzene; 2,4,5-trichlorophenol, benzene hexachloride, o-dichlorobenzene and dioctyl phthalate.

Abstract: The distillative separation of methacrylic acid from isobutyric acid is significantly improved by the introduction into the distillation system of a third component selected from the group consisting of methyl methacrylate, methyl isobutyrate and dimethylformamide.

Abstract: n-Amyl acetate cannot be completely removed from n-amyl acetate - n-amyl alcohol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Amyl acetate can be readily removed from mixtures containing it, n-amyl alcohol and water by using extractive distillation in which the extractive distillation agent is a higher boiling organic compound or a mixture of these. Typical examples of effective agents are dimethylsulfoxide; N,N-dimethylacetamide and dimethylsulfoxide; dimethylformamide, N,N-dimethylacetamide and acetamide.

Abstract: Propanoic acid cannot be completely removed from propanoic-water mixtures by distillation because of the presence of the minimum azeotrope. Propanoic acid can be readily removed from mixtures containing it and water by using extractive distillation in which the extractive distillation agent is an acid amide. Typical examples of effective agents are acetamide; dimethylformamide and methyl glutaronitrile; formamide, adiponitrile and N,N-dimethylacetamide.

Abstract: Isopropanol cannot be completely removed from isopropanol - isopropyl acetate - water mixtures by distillation because of the presence of the minimum ternary azeoptrope. Isopropanol can be readily removed from mixtures containing it, isopropyl acetate and water by using extractive distillation in which the extractive agent is a higher boiling benzoate or nitro paraffin. Typical examples are methyl benzoate; methyl benzoate and nitromethane; butyl benzoate, nitromethane and nitroethane.

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: 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 hexahydrophthalic anhydride; methyl tetrahydrophthalic anhydride and pentanol-1; trimellitic anhydride, ethyl salicylate and resorcinol.

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: A process for recovering 3-methyl-1-butene from a hydrocarbon stream by treating the stream with a dimethylformamide/sulfolane solvent mixture to remove compounds which form azeotropes with 3-methyl-1-butene and separating the remaining stream.

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: N-propanol and allyl alcohol cannot be separated from each other by distillation because of the proximity of their boiling points. N-propanol can be readily separated from allyl alcohol 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 compound. Examples of effective agents are: dimethylsulfoxide; acetamide and ethylene glycol phenylether; adiponitrile; N,N-dimethylacetamide; dimethylformamide; and sulfolane.

Abstract: Methyl acetate cannot be completely removed from methyl acetate - methanol mixtures by distillation because of the presence of the minimum binary azeotrope. Methyl acetate can be readily removed from mixtures containing it and methanol 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 dimethylformamide; dimethylsulfoxide plus tetraethylene glycol, dimethylsulfoxide plus 1,5-pentanediol plus 1,6-hexanediol.

Abstract: n-Propyl acetate cannot be completely removed from n-propyl acetate - n-propanol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Propyl acetate can be readily removed from mixtures containing it, n-propanol and water 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. Examples of effective agents are N,N-dimethylacetamide; acetamide and triethylene glycol; acetamide and N,N-dimethylacetamide and triethanolamine.

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 comprises propoxypropanol; propoxypropanol and 1,4-butanediol; ethyl benzoate and ethylene glycol phenyl ether and benzyl alcohol.

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: Isopropyl ether cannot be completely removed from isopropyl ether-isopropanol-water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropyl ether can be readily removed from mixtures containing it, isopropanol and water by using extractive distillation in which the extractive distillation agent is dimethylsulfoxide with or without a mixture of higher boiling oxygenated and/or nitrogenous organic compounds. Typical examples are dimethylsulfoxide; dimethylsulfoxide and ethylene glycol; dimethylsulfoxide, dimethylformamide and 1,4-butanediol.

Abstract: A process for producing anhydrous ethanol from an ethanol-water mixture feedstock comprising subjecting the feedstock to distillation in a first distillation zone to produce an overhead vapor of from about 80 to about 90 weight percent ethanol, subjecting the thus produced overhead vapor to extractive distillation in an extractive distillation zone to produce anhydrous ethanol vapor overhead of about 99.5 weight percent ethanol and a solvent-rich bottom stream, and stripping the solvent-rich bottom stream and recycling the thus produced lean solvent bottom stream to the extractive distillation zone and recycling the thus produced overhead vapor stream to the first distillation zone. Also disclosed is a system for performing the process.

Abstract: Methanol cannot be completely removed from methanol-methyl acetate mixtures by distillation because of the presence of the minimum binary azeotrope. Methanol can be readily removed from mixtures containing it and methyl acetate by using extractive distillation in which the extractive distillation agent is a higher boiling oxygenated or nitrogenous organic compound or a mixture of these. Typical examples of effective agents are: ethylene glycol phenyl ether, ethylene carbonate, nitromethane, 2-nitrotoluene, 1-nitropropane plus propylene carbonate.

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 and/or nitrogenous organic compound or a mixture of these. Typical examples of effective agents are adiponitrile; ehtylene carbonate plus dimethylformamide; adiponitrile plus dimethylformamide plus glycerine.

Abstract: n-Butyl acetate cannot be completely removed from n-butyl acetate - n-butanol - water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Butyl acetate can be readily removed from mixtures containing it, n-butanol and water 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 dimethylsulfoxide; dimethylsulfoxide and 1,4-butanediol; dimethylsulfoxide, dimethylformamide and 1,6-hexanediol.

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: Isopropyl ether cannot be completely removed from isopropyl ether-isopropanol-water mixtures by distillation because of the presence of the minimum ternary azeotrope. Isopropyl ether can be readily removed from mixtures containing it, isopropanol and water 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 ethylene glycol; dimethylsulfoxide plus propylene glycol; dimethylsulfoxide plus dimethylformamide plus diethylene glycol diethyl ether.

Abstract: An improvement of a method for purifying 1,2-dichloroethane by passing through a distillation column a crude 1,2-dichloroethane produced by oxychlorination of ethylene with at least one of a crude 1,2-dichloroethane produced by direct chlorination of ethylene and a crude uncracked 1,2-dichloroethane recovered in thermal cracking of 1,2-dichloroethane, the improvement which comprises feeding the oxychlorination-produced 1,2-dichloroethane to an upper plate of the distillation column which is above a plate of the column to which at least one of the direct chlorination-produced 1,2-dichloroethane and the uncracked 1,2-dichloroethane is fed, and recovering 1,2-dichloroethane as a bottom product. The purification method is very useful in the production of vinyl chloride by thermal cracking of 1,2-dichloroethane since carbon tetrachloride effective as a thermal cracking catalyst is recovered in concentrations stabilized within the range of .+-.500 p.p.m.

Abstract: n-Butyl acetate cannot be completely removed from n-butyl acetate-n-butanol--water mixtures by distillation because of the presence of the minimum ternary azeotrope. n-Butyl acetate can be readily removed from mixtures containing it, n-butanol and water 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 N,N-dimethylacetamide, dimethylsulfoxide and acetamide, ethylene glycol propylene glycol, dimethylsulfoxide and acetamide.

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: 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.