Abstract: Methods for the selective hydrogenation of acetylenic compounds in a product stream that includes isoprene. A method of selectively hydrogenating an acetylenic hydrocarbon in the presence of isoprene may include obtaining a hydrocarbon mixture comprising an acetylenic hydrocarbon, isoprene, and butadiene or cyclopentadiene, or both. If cyclopentadiene is present, the hydrocarbon mixture may comprise greater than 2 wt. % cyclopentadiene. The method may further include contacting the hydrocarbon mixture and hydrogen (H2) with a hydrogenation catalyst under reaction conditions that are more selective to the hydrogenation of the acetylenic hydrocarbon than the isoprene.

Abstract: The disclosure relates to a process for separating propylene oxide for a crude propylene oxide stream, for example an intermediate stream from a PO/TBA process. The crude propylene oxide stream can be passed through an extractive distillation column. The distillation column is operated at a pressure in a range of greater than 25 up to 50 psig, and/or at a temperature in a range of from 70 to 150 degrees Celsius using C8-C20 paraffin as extractive solvent with an overhead distillate water wash drum. The crude propylene oxide stream include from 0.001 to 0.1 wt % methanol, based on the total composition of the crude propylene oxide stream. The systems, methods, and apparatuses can produce a propylene oxide stream having less formaldehyde and acetaldehyde than the prior art.

Abstract: A method is described for controlling instability of operation in a de-ethanizer tower (13) in the gas recovery unit in fluid catalytic cracking units and delayed coking units. The method comprises the step of intervening in the de-ethanizer tower (13) when instability occurs in it, and adjusting the material balance of water in such a way that the excess of water in the feed load stream (9) is removed only as an azeotrope. The intervention is performed by introducing into the feed load stream (9) of the de-ethanizer tower (13) a volume fraction (18) of a flow of hydrocarbon, which may be either dry hydrocarbons or hydrocarbons with a low level of water content.

Abstract: Disclosed are a process and an apparatus for using an olefin as an azeotropic entrainer to isolate a target organic compound from a waste stream. The olefin may be, for example, 1-decene, 1-dodecene, or 1-tetradecene. The target organic compound may be 1,3-dichloro-2-propanol in waste stream comprising a 2,2?-oxybis(1-chloropropane).

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: In an acetonitrile recovery process a waste stream containing methanol and acetonitrile is mixed with hexane and distilled to form a condensate having two layers, a top layer of containing hexane and a bottom layer of methanol and acetonitrile, where selective removal of one or both of these layers allows for a column bottoms product containing at 98 wt. % acetonitrile to be recovered.

Abstract: The invention relates to methods for separating mixture components such as reactor effluent components. In particular, the invention relates to the use of an extractive agent such as a hydrocarbon in an extractive distillation process to separate monomers such as a C4-C7 isoolefins such as isobutylene from mixtures such as reactor effluents including one or more hydrofluorocarbon(s) (HFC).

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: The present invention provides a process for removing methyl acetylene and/or propadiene from a propylene stream and/or a butylene stream by two step fractionation. Methyl acetylene and/or propadiene avoids the use of a hydrogenation reactor and makes the methyl acetylene and/or propadiene recoverable from the process.

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: An assembly of trays in a divided wall column having an inner column wall, a dividing wall, and an interior space includes: a first tray having at least one radial downcomer adjacent the dividing wall and extending radially toward the inner column wall a first substantial distance, and a first liquid receiving area having a radial axis at a first angle to the dividing wall and extending radially toward the inner column wall a second substantial distance; and a second tray below the first tray, the second tray having at least one other downcomer having a radial axis at a second angle to the dividing wall and extending radially toward the inner column wall a third substantial distance, and at least one second liquid receiving area adjacent the dividing wall and extending radially toward the inner column wall a fourth substantial distance.

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 process is described for purifying propylene oxide, which includes the step of distilling propylene oxide containing impurities in the presence of a hydrocarbon having 5 carbon atoms or less. According to the present invention, a process is provided for purifying propylene oxide which has a feature that impurities contained in a solution containing propylene oxide to be purified can be efficiently removed. Oxygen-containing impurities, in particular, can be very efficiently removed.

Abstract: The present invention aims to isolate the azeotropes formed in a distillation column (B1) by methanol, propane and butane. The azeotropes are then liquefied in heat exchanger (E2) and mixed in contactor (M1) with water in order to dissolve the methanol in water. The mixture is then fed into a decantation tank (D2) to separate the aqueous phase from the liquid hydrocarbon phase. Finally, an aqueous phase containing methanol is discharged and the methanol-depleted hydrocarbon phase is recycled to distillation column (B1) as reflux.

Abstract: The present invention involves processes that utilize an olefinic compound, in particular, hexafluoropropene (HFP) or chlorotrifluoroethene (CFC-1113) as extracting agents in the purification of pentafluoroethane (HFC-125). These processes can utilize recovered HFP as a precursor for the production of heptafluoropropane (HFC-227) or other derivatives.

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: Disclosed is a process for the recovery and purification of 3,4-epoxy-1-butene (epoxybutene) from mixtures comprising epoxybutene and aliphatic and aromatic hydrocarbons containing five to seven carbon atoms having boiling points between about 20° C. and 115° C. by means of extractive distillation of the epoxybutene using certain extractive distillation solvents.

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 mixture of propylene oxide and methanol is separated by liquid/liquid extraction using water and a hydrocarbon such as n-octane as extractive solvents.

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: Nitrogen trifluoride (NF3) containing less than 10 parts-per-million molar impurities, e.g., tetrafluoromethane (PFC-14), is disclosed. Azeotropic and extractive distillation processes using entraining agents for separating NF3 and PFC-14 from each other and from mixtures with other electronics industry materials are disclosed.

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 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: 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: Process for the recovery of fluorinated sulphonic acid including the step of subjecting the spent acid to heat treatment with stepwise or continuously increasing temperature, withdrawing at least two fractions during the heat treatment; and recovering the fluorinated sulphonic acid from each fraction.

Abstract: For the fractionation of viscous silicones, oily or polymeric diorganosilicones with a chain length of between 2 and 10 000 are separated into a top and a bottom product, preferably continuously in an extracting column, using compressed hydrocarbons such as ethane, propane and n- or i-butane, or mixtures thereof, at temperatures of between 25 and 250° C., pressures of between 20 and 500 bar and a gas density >160 kg/m3. To avoid viscosity problems, either an organic solvent in the form of a C5-8 alkane or up to 85 wt. % of the compressed gas (mixture) can be added to the starting materials prior to fractionation. With this process, high-quality viscous silicone fractions are obtained, which have a chain length of 200 to 10 000 and/or a viscosity of 100 to 500 000 mPas, and whose total oligomer content D4 to D20 is less than 0.05 wt. %.

Abstract: Gamma-Butyrolactone (GBL) is recovered from a mixture containing GBL and other heavy organics by a process of azeotropic distillation in the presence of a C8-C 10 hydrocarbon as an azeotroping agent, wherein an azeotrope of GBL and the hydrocarbon is obtained as a distillate, which forms immiscible GBL-rich and hydrocarbon-rich phases, and the hydrocarbon-rich phase is decanted or isolated from the GBL-rich phase. By this process GBL can be efficiently separated from a large proportion of various compounds having boiling points close to that of GBL, e.g., the methyl-&ggr;-butyrolactones (MeGBL's).

Abstract: A purification process of pentafluoroethane from a crude pentafluoroethane containing chloropentafluoroethane as a by-product by extractive distillation using an extracting reagent having a standard boiling point of from −10° C. to 100° C. and being selected from paraffinic hydrocarbons, alcohols, ethers, esters, and ketones.

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: 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: A process for the separation of propylene from an input stream of C3 hydrocarbons containing propylene and methyl acetylene and/or propadiene and, optionally, C4 and/or higher hydrocarbons is described. The process includes subjecting the input stream to fractional distillation to separate propylene as an overhead stream leaving a bottoms stream containing the methyl acetylene and/or propadiene and the C4 and/or higher hydrocarbons, when present. A propane-containing stream is added to said input stream whereby propane is separated as part of the bottoms stream. The propylene content of the bottoms streams is maintained at less than 10% weight. The amount of propane added to the input stream is such that the weight of propane, propylene, and C4 and/or higher hydrocarbons, when present, in the bottoms stream is greater that the total weight of methyl acetylene and propadiene in the bottoms stream.

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: A process for the continuous distillation of thermolabile monomers under reduced pressure in a column includesfeeding the thermolabile monomers in vapor or liquid form to the column,introducing an inert distillation aid which forms a heteroazeotrope with the thermolabile monomers into the vaporizer at the bottom of the column, but separately from the monomer feed, and vaporizing into there or feeding an emulsion of thermolabile monomers and an inert distillation aid into the vaporizer or into the column,condensing the azeotrope at the top of the column and separating it in a phase separator, taking off the thermolabile monomers and returning the distillation aid to the column or, if desired, working it up by distillation andtaking off components having a higher boiling point than the thermolabile monomers from the bottom of the column.

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: 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: A process for the purification of 1-chloro-1,2,2,2-tetrafluoroethane (F124) containing 1,2-dichlorotetrafluoroethane (F114) and/or 1,1-dichlorotetrafluoroethane (F114a). The F124 to be purified is subjected to extractive distillation, the extractant being chosen from C.sub.5 -C.sub.8 aliphatic or cycloaliphatic hydrocarbons and C.sub.4 -C.sub.8 perfluoroalkyl halides.