Abstract: Systems and methods for separating an alcohol, and in particular butanol, from a fermented feed and concentrating thin stillage into syrup includes operation of one or more alcohol recovery distillation columns using the heat supplied by steam generated from concentration of the thin stillage in a multi-train, multi-effect evaporation system.

Abstract: Processes for the preparation and purification of hydrofluoroolefins such as tetrafluorinated propenes. A process is provided for separating a first hydrofluoroolefin from a second hydrofluoroolefin by a) providing a mixture including a first hydrofluoroolefin and a second hydrofluoroolefin, which first hydrofluoroolefin is preferentially more reactive with an amine than the second hydrofluoroolefin; b) adding a sufficient amount of an amine to the mixture to form a combination including the second hydrofluoroolefin and a reaction product of the first hydrofluoroolefin and the amine; and then c) separating the reaction product from the combination. This is particularly useful for removing 1,2,3,3,3-pentafluoropropene (HFO-1225ye) impurities from the hydrofluoroolefin 2,3,3,3-tetrafluoropropene (HFO-1234yf). HFO-1234yf is a refrigerant with low global warming potential.

Abstract: The invention relates to a method for removing water from a mixture containing at least one compound having at least one group reactive towards isocyanate and containing water, the mixture being applied to the surface of a rotating body A, the mixture flowing over the surface of the rotating body A to an outer region of the surface of the rotating body A and water evaporating from the mixture. In particular, this method is suitable for removing water from alcohols and amines.

Abstract: A process for the separation of the aromatic compounds benzene, toluene and xylene from an aromatics-containing reformate gasoline and pyrolysis gasoline or a coke-oven light oil or an aromatics-containing refinery stream, in which the aromatics are separated by an extractive distillation uses a novel solvent combination made up of the compounds n,n?-diformyl piperazine or 2,2?-bis-(cyanoethyl)ether in a combination with n-formyl morpholine as a second solvent for extractive distillation so that the solvent combination obtained shows a higher selectivity with regard to the aromatics to be extracted so that a lower solvent load is required. The aromatics-containing feed mixture is first submitted to a pre-distillation so that the obtained fraction has a narrow boiling point range. This fraction is then submitted to an extractive distillation in a first column, in which an aromatics-lean head product of predominantly paraffinic hydrocarbons is obtained as well as an aromatics-enriched bottom product.

Abstract: Disclosed is a method for separating, with a multi-stage distillation column, a mixture containing an active hydrogen-containing compound (A) and a compound (B) that reversibly reacts with the active hydrogen containing compound (A), the method comprising distillation-separating the active hydrogen-containing compound (A) and the compound (B) with the multi-stage distillation column in the presence of an intermediate-boiling-point inactive compound (C) that has a normal boiling point between a normal boiling point of the active hydrogen-containing compound (A) and a normal boiling point of the compound (B) and is chemically inactive for both of the (A) and the compound (B).

Abstract: A process and system for removing bound water from bio-oil by azeotropic distillation. The process includes combining a bound-water-containing bio-oil with an azeotrope agent and subjecting the resulting treated bio-oil to azeotropic distillation under reduced pressure. The azeotropic distillation removes a substantial portion of the bound water from the bio-oil, thus producing a water-depleted bio-oil that is less corrosive, more stable, and more readily miscible with hydrocarbons.

Abstract: Oxidation of an alkane to an alkanone in a process stream forms aldehyde-based impurities. A method of minimizing the aldehyde-based impurities introduces an amine into the process stream to minimize the aldehyde-based impurities. The amine interacts with the alkanone and the aldehyde-based impurities thereby forming heavy products. The method separates the heavy products from the alkanones to reduce a level of the aldehyde-based impurities. The process stream preferably includes cyclohexyl ketone as the alkanone and n-hexanal as the aldehyde-based impurity. The method is typically involved in synthesis of a caprolactam.

Abstract: An energy-efficient extractive distillation process for producing anhydrous ethanol from aqueous/ethanol feeds containing any range of ethanol employs an extractive distillation column (EDC) that operates under no or greatly reduced liquid reflux conditions. The EDC can be incorporated into an integrated process for producing anhydrous ethanol used for gasoline blending from fermentation broth. By using a high-boiling extractive distillation solvent, no solvent, is entrained by the vapor phase to the EDC overhead stream, even under no liquid reflux conditions. The energy requirement and severity of the EDC can be further improved by limiting ethanol recovery in the EDC. In this partial ethanol recovery design, ethanol which remains in the aqueous stream from the EDC is recovered in a post-distillation column or the aqueous stream is recycled to a front-end pre-distillation column where the ethanol is readily recovered since the VLE curve for ethanol/water is extremely favorable for distillation.

Abstract: A process for debottlenecking a system for the separation of a conjugated diolefin the system including a first extraction section having an extractive distillation column and a stripping column and a second extraction section. The process includes the steps of withdrawing a first portion of an extract from the extractive distillation column, the extract having at least the first portion and a second portion, and transferring the first portion of the extract to a flash/separation vessel; separating the first portion of the extract into a vapor phase and a liquid phase by flashing in a flash/separation vessel; and combining the liquid phase of the separated first portion of the extract with the second portion of the extract to produce an extract feed for further processing. A system and process for the separation of a conjugated diolefin from a C4- or C5-hydrocarbon mixture containing the conjugated diolefin and higher acetylenes are also provided.

Abstract: The present invention relates to a process for recovering components from a low boiler mixture which is obtained in the distillation of hydrogenation effluents from the preparation of polymethylols, by multistage distillation of the low boiler mixture comprising a tertiary amine, water, methanol, polymethylol of the formula (I) methylolalkanal of the formula (II) alcohol of the formula (III) and an alkanal with a methylene group in the ? position to the carbonyl group, and in which each R is independently a further methylol group or an alkyl group having 1 to 22 carbon atoms or an aryl or aralkyl group having 6 to 22 carbon atoms, a first distillation stage involving separating the low boiler mixture into a higher-boiling, predominantly water-rich fraction and into a lower-boiling aqueous organic fraction comprising the tertiary amine, and the second distillation stage involving separating the aqueous organic fraction from the first distillation stage into a predominantly amine-containing fract

Abstract: A process for extractively removing homogeneously dissolved catalysts from a reaction effluent of a hydrocyanation of unsaturated mononitriles to dinitriles with a hydrocarbon H, including performing the steps of a) concentrating the reaction effluent before step b) by distillation at pressures of from 0.1 to 5000 mbar and temperatures of from 10 to 150° C., b) adding a hydrocarbon H to the concentrated reaction effluent to obtain a stream I, and c) feeding stream I, without prior separation of the liquid phases, into an extraction apparatus and extracting it at a temperature T with the hydrocarbon H to obtain a stream II comprising the hydrocarbon H enriched with the catalyst and a stream III having a low catalyst content.

Abstract: A process for separating trioxane from a feed stream I comprising formaldehyde, trioxane and water, in which a) a feed stream I comprising formaldehyde as main component and trioxane and water as secondary components is provided, b) the feed stream I, a recycle stream V and a recycle stream VII comprising formaldehyde as main component and water and trioxane as secondary components are fed into a first distillation stage and distilled at a pressure of from 0.1 to 2.5 bar to give a stream II comprising formaldehyde as main component and water as secondary component and a stream III comprising trioxane as main component and water and formaldehyde as secondary components and a stream X comprising water, trioxane and formaldehyde, c) the stream III is, if appropriate after removal of low boilers from the stream III in a low boiler removal stage, distilled in a second distillation stage at a pressure of from 0.2 to 17.5 bar, with the pressure in the second distillation stage being from 0.

Abstract: The invention relates to a process for purifying (meth)acrylates.

Abstract: A process for debottlenecking a system for the separation of a conjugated diolefin the system including a first extraction section having an extractive distillation column and a stripping column and a second extraction section. The process includes the steps of withdrawing a first portion of an extract from the extractive distillation column, the extract having at least the first portion and a second portion, and transferring the first portion of the extract to a flash/separation vessel; separating the first portion of the extract into a vapor phase and a liquid phase by flashing in a flash/separation vessel; and combining the liquid phase of the separated first portion of the extract with the second portion of the extract to produce an extract feed for further processing. A system and process for the separation of a conjugated diolefin from a C4- or C5-hydrocarbon mixture containing the conjugated diolefin and higher acetylenes are also provided.

Abstract: It is an object of the present invention to provide a process for producing easily polymerizable substance, which can realize stable operation of a purification system, and can stably maintain a production amount by avoiding production stoppage, upon production of an easily polymerizable substance in plural reactors. The present invention is directed to a process for producing easily polymerizable substance, which comprises mixing easily polymerizable substances obtained in plural reactors in advance, and supplying the mixture to a purification apparatus.

Abstract: The present invention concerns a process for providing tertiary amine products which are color-stable, and have a greatly reduced tendency to take on color during their storage. According to the invention, an ethyleneamine derivative is added to the distillation pot prior to or during the distillation of the tertiary amine product. Preferably, the ethyleneamine derivative has a higher boiling point than the desired tertiary amine product so as to preclude the ethyleneamine from distilling over with the tertiary amine.

Abstract: A process for the purification of fluoromethyl hexafluoroisopropyl ether which comprises contacting a crude composition comprising fluoromethyl hexafluoroisopropyl ether and hexafluoroisopropyl alcohol with a modifier in the presence of which the vapor pressure of the ether and/or the alcohol is modified whereby the difference in vapor pressure of the ether and the alcohol increases relative to the difference in vapor pressure of the ether and alcohol in the absence of the modifier and separating the ether from the alcohol.

Abstract: The present invention provides an industrially easy and economical method for purification of acrylic acid which enables to efficiently eliminate impurities from a crude acrylic acid containing aldehydes as the impurities while the formation of acrylic acid polymer is inhibited. The method for purification of acrylic acid includes the step of distilling a crude acrylic acid which is charged with an aldehyde treatment chemical, wherein the concentration ratio of furfural to acrolein by weight in the crude acrylic acid is adjusted so as to satisfy the following equation: (furfural concentration by weight)/(acrolein concentration by weight)?100.

Abstract: A process for the purification of fluoromethyl hexafluoroisopropyl ether which involves contacting a crude composition fluoromethyl hexafluoroisopropyl ether and hexafluoroisopropyl alcohol with a modifier to modify the vapour pressure of the ether and/or the alcohol. The difference in vapour pressure of the ether and the alcohol increases relative to the difference in vapour pressure of the ether and alcohol in the absence of the modifier and enables separation of the ether from the alcohol. The modifier suitably is ammonia and/or an amine.

Abstract: The invention relates to a process for preparing colourless dibenzylamine by adding ammonium chlorides or amines to the industrially obtained dibenzylamine and subsequent distillation.

Abstract: There is described a process for the extraction of at least one relatively polar component from a material which may be naturally occuring or a synthetic mixture, the process comprising the steps of: (a) contacting the material with a solvent mixture comprising a C1 to C4 fluorinated hydrocarbon, especially 1,1,1,2-tetrafluoroethane and a co-solvent having a dielectric constant (at 20° C.) of at least 5; and (b) separating the charged solvent from said material, thereby to isolate said material.

Abstract: There is described a process for the extraction of a least one relatively polar component form a material which may be naturally occurring or a synthetic mixture, the process comprising the steps of: (a) contacting the material with a solvent mixture comprising C1 to C4 fluorinated hydrocarbon, especially 1,1,1,2-tetrafluorethan and a co-solvent having a dielectric constant (at 20° C.) of at least 6 so as to charge the solvent mixture wherein the co-solvent is selected from the group consisting of amides, sulfoxides, alcohols, ketones, organic acid, carboxylic acid derivatives, cyanide derivatives, ammonia sulfur containing molecules, inorganic acids and nitro derivatives and separating the charged solve mixture from the material to isolate the polar component.

Abstract: A process for the recovery and purification of cyclobutanone from a crude product mixture obtained from an oxidation product mixture resulting from the oxidation of cyclobutanol to cyclobutanone in the presence of water. The process provides for the recovery of cyclobutanone in a purity of at least 90 weight percent by a combination of distillation steps.

Abstract: A method of separating methanol and acetone, and methanol and methyl acetate involves distilling a mixture of the components by an extractive distillation process in the presence of an extractive distillation solvent. The extractive distillation solvent may be an amine, a chlorinated hydrocarbon, a brominated hydrocarbon, a paraffin, and an alkylated thiopene.

Abstract: A method of separating ethanol and ethyl acetate, and ethanol and water involves distilling a mixture of the components by an extractive distillation process in the presence of an extractive distillation solvent. The extractive distillation solvent may be an amine, an alkylated thiopene, and paraffins.

Abstract: The present invention provides a process for recovering ditrimethylolpropane from a still residue obtained by extracting and then distilling off trimethylolpropane from a reaction solution obtained by reacting n-butyraldelhyde with formaldehyde in the presence of a basic catalyst, wherein the still residue is distilled to remove high-boiling components therefrom, and the resultant distillate is subjected to crystallization. When the above process is combined with the acid decomposition, it becomes possible to decompose a linear formal compound obtained from 2 molecules of TMP contained in the still residue as crude TMP and one molecule of formaldehyde, so that di-TMP having a higher purity is obtained.

Abstract: Process for purifying acrylic acid in order to remove the polymer-type impurities in those places in the distillation columns in which they have a tendency to accumulate, and more particularly a process directed towards removing the polymeric impurities which are formed during a step for removing the aldehyde impurities from acrylic acid, according to which step the medium containing the acrylic acid to be purified is distilled by adding to this medium at least one amino compound of hydrazine type and by flushing away, at the foot of the distillation column, the heavy compounds formed by the said hydrazine-type amino compound(s) with the impurities. According to the invention, the acrylic acid to be purified is also distilled in the presence of at least one compound from the class of nonionic surface agents and of at least one polymerization inhibitor. Polysaccharide ethers and acetates, in particular ethers derived from cellulose or starch, may be mentioned as nonionic surface agents.

Abstract: In a process for the separation by rectification of (meth)acrylic acid from a mixture containing (meth)acrylic acid and an inert hydrophobic organic liquid having a boiling point higher than that of (meth)acrylic acid as main constituents and also lower aldehydes as secondary constituents, a primary amine and/or a salt thereof are added.

Abstract: Crude (meth)acrylic acid is purified by a process in which a primary amine compound and an organic sulfonic acid are added to the crude (meth)acrylic acid and the latter is then worked up by distillation.

Abstract: The present invention concerns a method for producing acrylic acid which involves subjecting an acrylic acid-containing aqueous solution obtained by catalytic vapor phase oxidation of propylene and/or acrolein to evaporation whereby an acrylic acid-containing vapor is obtained; and subjecting the acrylic acid-containing vapor to azeotropic dehydration. The present invention offers a number of advantages including a reduce amount of polymer that may adhere to the surface of an azeotropic dehydration column, a low-blowing separation column or an in a high-boiling separation column in a plant for producing acrylic acid. Consequently, the production plant can be operated for a long time without stopping operations.

Abstract: Inhibition of the formation of unsaturated carbon compounds during the heating of 141b involving the addition of various inhibitors such as dialkylhydroxylamine and/or the use of a vessel made of a nickel alloy.

Abstract: A process for recovering hexamethylenediamine (I) from a mixture (II) including(I) hexamethylenediamine,(III) hexamethyleneimine,(IV) a compound selected from 2-aminomethylcyclopentylamine and 1,2-diaminocyclohexane,(V) an imine,(VI) adiponitrile and 6-aminocapronitrileincludes distilling(a) a mixture (II) to obtain(a1) a low boiling fraction (III),(a2) a medium boiling fraction (VII) (I), (IV) and (V), and(a3) a high boiling fraction (V) and (VI),(b) a mixture (VII) to obtain(b1) an overhead product (IV), and(b2) a mixture (VIII) (I) and (V) as bottom product, and(c) a mixture (VIII) to obtain(c1) (I) as overhead product, and(c2) a bottom product (V).

Abstract: Mesitylene is difficult to separate from 1,2,4-Trimethylbenzene because of the proximity of their boiling points. They are readily separated by azeotropic distillation. Effective agents are isopropyl acetate, 2-pentanol and acetonitrile.

Abstract: A method for improving purification efficiency when distilling off aldehyde contaminants during chemical manufacturing processes by adding a substituted aromatic amine having electron donating group substituents prior to the distillation column. The method is particularly useful for removal of aldehydes such as acrolein, generated as a by-product of acrylonitrile manufacture. Preferred aromatic amines are 2-amino aniline, 3,4-dimethyl aniline and 4-ethyl aniline.

Abstract: Inhibition of the formation of unsaturated carbon compounds during the heating of 141b involving the addition of various inhibitors such as butylene oxide and/or the use of a vessel made of a nickel alloy.

Abstract: 3-Methyl-2-pentenal cannot be separated from 1-butanol by conventional rectification because of the proximity of their boiling points. 3-methyl-2-pentenal can be readily separated from n-butanol by azeotropic distillation. Effective agents are dimethoxymethane, petroleum ether and tetramethylortho-silicate.

Abstract: Mesitylene cannot be separated from 4-ethyl toluene by distillation because of the proximity of their boiling points. They are readily separated by azeotropic distillation. Effective agents are isopropyl palmitate, triacetin and methyl salicylate.

Abstract: 2-Methyl-1-butanol and 3-methyl-1-butanol are difficult to separate from 1 pentanol by conventional distillation or rectification because of the proximity of their boiling points. 2-Methyl-1-butanol and 3-methyl-1-butanol can be easily separated from 1-pentanol by extractive distillation. Effective agents are 3-carene, propylene glycol phenyl ether and dimethylsulfoxide.

Abstract: Process for the recovery of pure hydrocarbons from a hydrocarbon mixture, more particularly, a high aromatics content hydrocarbon mixture, by extractive distillation in an extractive distillation column. A first solvent feed for a first sub-flow of a selective solvent is provided between the top part of the column and the bottom part thereof. The selective solvent used is an N-substituted morpholine. Substantially non-aromatics are withdrawn as the raffinate from the head of the extractive distillation column and substantially aromatics and selective solvent are withdrawn as the extract from the sump of the extractive distillation column. A second sub-flow of the selective solvent is introduced via a second solvent feed in the top part of the column above the first solvent feed. The quantity of solvent supplied with the second sub-flow constitutes less than 50% of the total quantity of solvent.

Abstract: A process for the purification of recovered or regenerated phosphorus oxychloride contaminated by reactive organic compounds, by reacting the contaminated phosphorus oxychloride with from 0.1 to 5% by weight of an organic amine, having 1 or 2 tertiary N-atoms and a boiling point above the boiling point of phosphorus oxychloride, at the boiling temperature of the reaction mixture and subsequently carrying out fractional distillation at atmospheric pressure to obtain purified phosphorus oxychloride.

Abstract: A process for the separation by rectification of (meth)acrylic acid from a mixture containing (meth)acrylic acid and an inert hydrophobic organic liquid having a boiling point higher than that of (meth)acrylic acid as main constituents and also lower aldehydes as secondary constituents, a primary amine and/or a salt thereof are added.

Abstract: T-Amyl alcohol cannot be separated from n-butanol by distillation or rectification because of the closeness of their boiling points. T-Amyl alcohol is readily separated from n-butanol by extractive distillation. Effective agents are dimethylsulfoxide, N.N.dimethyl formamide and ethanolamine.

Abstract: Inhibition performance is improved in styrene processing through the addition of a stable nitroxide free radical compound to the styrene feed and to the reflux of at least one column.

Abstract: t-Amyl alcohol cannot be separated from n-butanol by distillation or rectification because of the closeness of their boiling points. t-Amyl alcohol is readily separated from n-butanol by azeotropic distillation. Effective agents are propyl acetate, tetrahydrofuran and heptane.

Abstract: Acetone cannot be separated from a mixture of isopropanol and water because of the closeness of their boiling points. Acetone can be easily separated from isopropanol and water by extractive distillation. Effective extractive agents are 1-nitropropane, 3-carene, dimethylsulfoxide and 3-pentanone.

Abstract: A process for the separation of dimethyl ether and chloromethane in mixturesA process for the separation of dimethyl ether and chloromethane in mixtures by two distillation steps. In the first step, the mixture is subjected to an extractive distillation with water, aqueous salt solutions or organic liquids as extractant, the top product being chloromethane. In the second step, the dimethyl ether is separated from the extractant.

Abstract: 2-Butanol cannot be sparated from t-amyl alcohol by distillation or rectification because of the closeness of their boiling points. 2-Butanol is readily separated from t-amyl alcohol by extractive distillation. Effective agents are butyl ether, benzyl acetate and 1,2,4-trimethyl benzene.

Abstract: Methyl ethyl ketone cannot be separated from ethanol by distillation or rectification because of the closeness of their boiling points. Methyl ethyl ketone is readily separated from ethanol by extractive distillation. Effective agents are methyl benzoate, phenol, glycerol and nitroethane.

Abstract: 3-Carene is difficult to separate from limonene by conventional distillation or rectification because of the proximity of their boiling points. 3-Carene can be readily separated from limonene by extractive distillation. Effective agents are o-cresol, 2,6-dimethyl-4-heptanone and triethylene glycol.

Abstract: A process for distilling a crude acrylic silane solution particularly containing impurities in a commercial scale for separating acrylic silane in the presence of a hindered phenol and/or amine as polymerization inhibitor, the process being improved by using simultaneously a dialkyldithiocarbamic acid copper and/or N-nitrosophenylhydroxylamine salt as synergistic polymerization inhibitor.