Abstract: The present disclosure provides high-grade ethanol production systems and methods that increase energy efficiency as compared to typical systems and methods by minimizing undesired acetal formation. The provided ethanol production method may include a low boilers removal distillation column and/or a stripper column constructed to simultaneously remove at least a portion of the acetaldehyde and at least a portion of the acetal from a feed stream in the presence of water. In some aspects, a low boilers removal process may be followed by a water removal process, which may be followed by a high boilers removal process. Acidity (e.g., carbon dioxide) may also be removed from a feed stream prior to or during the low boilers removal process. By minimizing acetal production, the provided method minimizes the amount of energy that is required to remove acetal when producing high-grade ethanol.

Abstract: Disclosed is a method for purifying phenol, by which the loss of a heat source is minimized, the amount used of steam is decreased, and efficiency of energy consumed in a process may be maximized. The method for purifying phenol includes a step of passing impurities including phenol, acetone and hydrocarbon, which are prepared using cumene as a raw material, via a plurality of distillation columns one by one, and performing azeotropic distillation, wherein the ratio of phenol and water at the uppermost end of the distillation column where the azeotropic distillation is performed, is from 60:40 to 65:35, for the optimized separation of the hydrocarbon.

Abstract: The present invention relates to a method for purifying phenol, which comprises: supplying a feed comprising phenol, acetone, hydroxyacetone and water to a distillation column at 60° C. to 95° C.; separating the feed into a first fraction, which comprises the acetone, and separates to the upper part of the distillation column and a second fraction, which comprises the phenol, and separates to the lower part of the distillation column; and recovering the first fraction and the second fraction, respectively.

Abstract: A novel minimum boiling binary azeotrope of n-undecane and n-butyl-3-hydroxybutyrate is shown to have utility as a solvent for degreasing of both nonpolar and polar contaminants. The components of the azeotrope are stable against degradation and the composition is largely invariant with pressure, yielding a unique solvent that can be used in cold cleaning and in vapor degreasing at elevated temperatures and over a wide range of pressures.

Abstract: Subject of the invention is a process for the production of methylbutynol, wherein the process comprises at least one pervaporation step. In a preferred embodiment, the process comprises the steps of (a) providing a feed composition comprising methylbutynol and water, (b) subjecting the feed composition to distillation in a distillation device, (c) removing a sidestream from the distillation device, the sidestream having a higher water content than the feed composition, and (d) subjecting said sidestream to pervaporation, thereby reducing the water content. The invention also relates to uses and devices relating to the inventive process.

Abstract: The invention relates to a process for purifying trifluoromethanesulfinic acid by azeotropic distillation with an aromatic solvent, to processes for preparing purified trifluoromethanesulfinic acid and to the use of the purified trifluoronnethanesulfinic acid for preparing trifluoromethylsulfinylated pyrazole derivatives, especially fipronil.

Abstract: Process for distillatively purifying polymerizable compounds using a high-boiling, inert, thermally long-term-stable substance as a boiling oil, characterized in that the boiling oil is disposed in the bottom of a rectification column.

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: 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: The invention relates to a process for purifying trifluoromethanesulfinic acid by azeotropic distillation with an aromatic solvent, to processes for preparing purified trifluoromethanesulfinic acid and to the use of the purified trifluoronnethanesulfinic acid for preparing trifluoromethylsulfinylated pyrazole derivatives, especially fipronil.

Abstract: Process for distillatively purifying polymerizable compounds using a high-boiling, inert, thermally long-term-stable substance as a boiling oil, characterized in that the boiling oil is disposed in the bottom of a rectification column.

Abstract: A method for recovering a solvent from its mixture containing oligomers extracted from grafted polyolefins is disclosed. The method includes distilling the solvent from the mixture in the presence of a naphthalene compound. The method of the invention significantly increases the solvent recovering yield without causing the vessel fouling.

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

Abstract: A process for the removal of aromatic compounds from the olefin feed to a sulfuric acid paraffin alkylation by feeding a olefin containing hydrocarbon stream and a dilute alkylate stream from a paraffin alkylation to a distillation zone and removing unreacted material from said hydrocarbon stream as overheads and removing a more concentrated alkylate product stream and a portion of said aromatic compounds as bottoms and the improved alkylation process resulting therefrom.

Abstract: A novel method for connecting multiple existing columns which are retrofitted into vapor-liquid contacting devices with trays or packings suitable for the operation of a three-phase (vapor-liquid-liquid) extractive distillation column for aromatics recovery. The retrofitted columns are connected by a vapor transfer line to transfer the vapor phase from the top of the lower column to the bottom of the upper column, and by a liquid transfer line to transfer the liquid phase from the bottom of the upper column to the top of the lower column of the three-phase extractive distillation column.

Abstract: The present invention provides extractive distillation processes for removing difluoromethane (HFC-32) from a mixture comprising HFC-32 and at least one of chlorodifluoromethane (CFC-12), 1,1,1-trifluoroethane (HFC-143a), chloropentafluoroethane (CFC-115), and pentafluoroethane (HFC-125) using hydrocarbon, chlorocarbon, and oxygen-containing extractive agents.

Abstract: The invention provides a method for producing purified N-vinyl-2-pyrrolidone free of odorous components. The method is composed of distilling with a distillation column a liquid, which is formed by adding to an odorous components-containing liquid having a N-vinyl-2-pyrrolidone purity of not lower than 90 wt %, a compound having boiling point lower than that of N-vinyl-2-pyrrolidone, and whereby removing the odorous components together with said low-temperature boiling compound as the distillate.

Abstract: Cyclic esters of hydroxy organic acids can be produced and recovered via azeotropic distillation. In certain embodiments cyclic esters, such as glycolide and lactide, can be produced from a fermentation broth or other feed stream that contains a hydroxy organic acid, an ammonium salt of a hydroxy organic acid, an amide of a hydroxy organic acid, or an ester of a hydroxy organic acid using azeotropic distillation. The hydroxy organic acid of the feed stream or the hydroxy organic acid derived from the feed stream by decomposition is reacted to produce the cyclic ester. In other embodiments a crude composition of a cyclic ester of an organic ester can be purified using azeotropic distillation.

Abstract: Disclosed herein are methods for the recovery of at least one of an organic acid or an organic acid amide, such as a heat stable lactic acid or lactamide, from a feed stream which contains the organic acid and/or organic acid amide. The feed stream is mixed with at least one azeotroping agent. The azeotroping agent is a hydrocarbon capable of forming at least one heteroazeotrope with the organic acid or the organic acid amide in the feed stream. The mixture of the feed stream and the azeotroping agent is heated to produce a vapor stream. The heteroazeotrope is a component of that vapor stream. The vapor stream can be heated further to separate components or it can be condensed into a liquid stream. The liquid stream is capable of being separated into a first phase and a second phase. The first phase contains the highest concentration of the organic acid and/or the organic acid amide and the azeotroping agent is part of the second phase.

Abstract: Disclosed herein are methods for the recovery of an organic acid, such as a heat stable lactic acid, from a feed stream which contains at least one of an organic acid amide, an organic acid ammonium salt, or an alkylamine-organic acid complex. The feed stream is mixed with at least one azeotroping agent. The azeotroping agent is a hydrocarbon capable of forming at least one azeotrope with the organic acid that is produced by the thermal decomposition of the amide, ammonium salt, or complex in the feed stream. Preferably the azeotrope is a heteroazeotrope. The mixture of the feed stream and the azeotroping agent is heated to produce a vapor stream. The azeotrope is a component of the vapor stream. The vapor stream can be condensed to a liquid stream, and the organic acid is recovered in the liquid stream that is produced. When the azeotrope is a heteroazeotrope, the vapor stream can be condensed into a liquid stream, which can be separated into a first phase and a second phase.

Abstract: A method for distilling a raw material liquid containing (meth)acrylic acid substantially free from azeotropic solvents, collected with a collection agent from a mixed gas obtained by gas phase catalytic oxidation reactions which includes feeding to a distillation column the raw material liquid which temperature is substantially equal to that of the entrance place in the column.

Abstract: A method of recovering acrylic acid from a mixture comprising acrylic acid, water and acetic acid is disclosed, which includes:

Abstract: A method of recovering acrylic acid from a mixture comprising acrylic acid, water and acetic acid is disclosed, which includes: (a) extracting acrylic acid from the mixture with a solvent mixture comprising ethyl acrylate as the preponderant component thereof and an organic co-solvent selected from the group consisting of toluene, heptane, 1-heptene, methylcyclohexane, cycloheptane, cycloheptadiene, cycloheptatriene, 2,4-dimethyl-1,3 pentadiene, methylcyclohexene and methylenecyclohexene to form an extracted composition; and (b) azeotropically distilling the extracted composition to recover acrylic acid.

Abstract: A process for reducing the level(s) of water and/or other impurities from cyclosiloxanes by either azeotropic distillation, or by contacting the cyclosiloxane compositions with an adsorbent bed material. The purified cyclosiloxane material is useful for forming low-dielectric constant thin films having dielectric constants of less than 3.0, more preferably 2.8 to 2.0.

Abstract: A process for purifying propylene oxide, which comprises distilling propylene oxide containing impurities in the presence of a hydrocarbon having 5 carbon atoms or less. According to the present invention, a process for purifying propylene oxide which has a feature that impurities contained in a solution containing propylene oxide to be purified can be efficiently removed, especially, oxygen-containing impurities can be very efficiently removed, is provided.

Abstract: Disclosed herein are methods for the recovery of an organic acid, such as a heat stable lactic acid, from a feed stream comprising at least one of an organic acid amide, an organic acid ammonium salt, or an alkylamine-organic acid complex. The feed stream that comprises the organic acid amide, organic acid ammonium salt, or alkylamine-organic acid complex is mixed with at least one azeotroping agent. The azeotroping agent is a hydrocarbon capable of forming at least one azeotrope with the organic acid that is produced by the thermal decomposition of the amide, ammonium salt, or complex in the feed stream. Preferably the azeotrope is a heteroazeotrope. The mixture comprising the feed stream and the azeotroping agent is heated to produce a vapor stream that comprises the azeotrope. The vapor stream can be condensed to a liquid stream, and the organic acid is recovered in the liquid stream that is produced.

Abstract: Disclosed herein are methods for the recovery of at least one of an organic acid or an organic acid amide, such as a heat stable lactic acid or lactamide, from a feed stream comprising the organic acid and/or organic acid amide. The feed stream that comprises the organic acid and/or organic acid amide is mixed with at least one azeotroping agent. The azeotroping agent is a hydrocarbon capable of forming at least one heteroazeotrope with the organic acid or the organic acid amide. The mixture comprising the feed stream and the azeotroping agent is heated to produce a vapor stream that comprises the heteroazeotrope. The vapor stream can be heated further to separate components or it can be condensed into a liquid stream. The liquid stream is capable of being separated into a first phase and a second phase. The first phase contains the highest concentration of the organic acid and/or the organic acid amide and the second phase comprises the azeotroping agent.

Abstract: A modular solvent recovery device (30) includes an enclosure (34) mounted to a frame (32) to enclose a tank (70) having a solvent section (72) and a waste fluid section (73), a still (40) in which waste photopolymer fluid is distilled by application of heat and vacuum pressure to the waste photopolymer fluid to distill a solvent from the waste photopolymer fluid and reduce the waste photopolymer fluid to a coalescing concentrated residue, and a flash-point-increasing agent delivery system (95) to supply a flash-point-increasing agent to the concentrated residue in an amount sufficient to raise the flash point temperature of the coalescing concentrated residue to a predetermined temperature. The still has a manhole device (46) comprising a pivotally and telescopically mounted closure (47) having wheels (51) rotatably mounted thereto and tracks (52) mounted to the still to engage the wheels and raise the closure vertically above a manhole (42) of the still upon pivotal movement of the closure.

Abstract: Cyclic esters of hydroxy organic acids can be produced and recovered via azeotropic distillation. In certain embodiments cyclic esters, such as glycolide and lactide, can be produced from a fermentation broth or other feed stream that comprises a hydroxy organic acid, an ammonium salt of a hydroxy organic acid, an amide of a hydroxy organic acid, or an ester of a hydroxy organic acid using azeotropic distillation. The hydroxy organic acid of the feed stream or the hydroxy organic acid derived from the feed stream by decomposition is reacted to produce the cyclic ester. In other embodiments a crude composition of a cyclic ester of an organic ester can be purified using azeotropic distillation.

Abstract: A method of removing water from wet organoborane by dissolving the wet organoborane in an organic solvent in which water is incompletely soluble, decanting any insoluble water, and distilling the organic phase to remove water which may be contained therein.

Abstract: A method for distilling a raw material liquid containing (meth)acrylic acid substantially free from azeotropic solvents, collected with a collection agent from a mixed gas obtained by gas phase catalytic oxidation reactions which includes feeding to a distillation column the raw material liquid which temperature is substantially equal to that of the entrance place in the column.

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 process is disclosed for manufacturing a concentrated residue from a photopolymer fluid which includes photopolymer and photopolymer solvent. The photopolymer fluid may be derived by chemically etching a photopolymer layer of a printing plate with a solvent. The process includes distilling the photopolymer fluid to recover the solvent and concentrate the photopolymer fluid to form a concentrated photopolymer residue, and mixing a flash-point-increasing agent with the concentrated photopolymer residue in an amount sufficient to raise the flash point temperature of the concentrated photopolymer residue to a pre-selected temperature to form the concentrated residue. The flash-point-increasing agent may be mixed with the waste photopolymer fluid prior, during, or after distillation. Also, the flash-point-increasing agent includes oils, such as paraffinic and naphthenic oils and a blend thereof.

Abstract: A process for recovering glycols from used glycol-containing technical fluids, especially from used antifreeze comprises adding to the used glycol-containing technical fluids an organic solvent which forms with the glycol to be separated off an azeotropic mixture which has a lower boiling point than the glycol itself and distilling off this azeotropic mixture.

Abstract: High purity tertiary butyl alcohol is obtained from mixtures comprised of tertiary butyl alcohol and tertiary butyl acetate by extractive distillation using a hydrocarbon extractive solvent such as decane.

Abstract: A method and apparatus for recycling and recovering potentially explosive solvents includes providing a contaminated solvent to a distillation tank, vaporizing the solvent in the distillation tank, thereby producing solvent vapor, condensing the solvent vapor, and adding a free radical scavenger substance to the distillation tank during the heating step. The vapor is then condensed and collected in a clean solvent tank where additional free radical scavenger substance is added to the clean solvent tank. Preferably, contaminated solvent is introduced into the solvent recovery system by providing contaminated solvent into contaminated solvent tank which is connected to the distillation tank, and an oxygen displacer substance is provided to the contaminated solvent tank and the clean solvent tank so as to minimize the amount of free oxygen in the tanks.

Abstract: The invention relates to a method for purifying a crude 1,1,1,3,3-pentafluoropropane (HFC-245fa) containing HFC-245fa and 1-chloro-3,3,3-trifluoro-trans-1-propene (HCFC-1233zd(t)), by distillation. This method is characterized in that the distillation is conducted in the presence of a solvent having a boiling point which is higher than that of HCFC-1233zd(t), thereby to substantially remove HCFC-1233zd(t) from the crude HFC-245fa. This solvent may be selected from carbon chlorides, chlorohydrocarbons, fluorochlorohydrocarbons, saturated hydrocarbons, and mixtures thereof. With the use of this solvent, it becomes possible to substantially easily separate HFC-245fa from HCFC-1233zd(t).

Abstract: 9,11- Diene C18 fatty acid cannot be separated from 10,12-Diene C18 fatty acid by conventional rectification because of the proximity of their boiling points. 9,11-Diene C18 fatty acid can be readily separated from 10,12-Diene fatty acid by azeotropic distillation. Effective agents are propyl formate, butyl ether, methyl pivalate and cyclopentanone.

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: 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: Cumene cannot be separated from 3-ethyl toulene by distillation because of the proximity of their boiling points. They are readily separated by azeotropic distillation. Effective agents are methyl salicylate, diethylene glycol butyl ether and 3-nitrotoluene.

Abstract: Ethyl acetate cannot be separated from ethanol by distillation or rectification because of the closeness of their boiling points. Ethyl acetate is readily separated from ethanol by azeotropic distillation. Effective agents are ethyl ether, methyl formate and cyclohexane.

Abstract: Natural cresylic acid is processed to remove neutral oil impurities by countercurrent liquid/liquid extraction using a heavy phase solvent of a mixture of glycerol and another polyhydric alcohol, preferably triethylene glycol. The light phase solvent is a light paraffinic or cycloparaffinic hydrocarbon.

Abstract: 2-Methyl-1-propanol cannot be separated from t-amyl alcohol by distillation or rectification because of the closeness of their boiling points. 2-Methyl-1-propanol is readily separated from t-amyl alcohol by azeotropic distillation. Effective agents are butyl propionate, cyclohexane and 2,2-dimethoxypropane.

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 method for separating hexamethylcyclotrisiloxane that does not require the use of a distillation set up adapted for use with solids and that collects the hexamethylcyclotrisiloxane in the form of an easy-to-handle solution. The method comprising inducing the ascent in the gaseous state of a hexamethylcyclotrisiloxane-containing mixture of polydimethylcyclosiloxanes in a distillation column provided with a sidestream element in the middle region of the column so as to induce the ascent of gaseous hexamethylcyclotrisiloxane to at least the level of the sidestream element, supplying into said distillation column solvent having a boiling point below that of hexamethylcyclotrisiloxane and capable of dissolving hexamethylcyclotrisiloxane, so as to form a liquid mixture of hexamethylcyclotrisiloxane and said solvent in the vicinity of the sidestream element, and withdrawing the said liquid mixture from the sidestream element.