Abstract: A process for operating a distillation column to separate an ethanol mixture comprising ethanol and acetic acid where the recovered ethanol comprises less than 700 wppm acetic acid. The operating conditions for the column may vary depending on the fed composition. In particular the process provides energy efficient recovery of ethanol with low concentration acetic acid.

Abstract: In one embodiment, the invention is to a process for producing ethanol, the process comprising the steps of carbonylating methanol in a carbonylation system in the presence of a carbonylation catalyst under conditions effective to form acetic acid; hydrogenating the acetic acid in a hydrogenation system in the presence of a hydrogenation catalyst to form a crude ethanol product comprising ethanol and water; separating the ethanol from the water to form an ethanol stream and a water stream; and directing at least a portion of the water stream to the carbonylation system, e.g., for use as an extractant in a permanganate reducing compound removal system.

Abstract: An integrated process for producing ethanol, comprising the step of reacting carbon monoxide with at least one reactant in a reactor containing a reaction medium to produce a liquid reaction product comprising acetic acid. The reaction medium comprises water, acetic acid, methyl acetate, a halogen promoter, and a first catalyst. The process further comprises the steps of directly feeding the liquid reaction product from the reactor to a distillation column and withdrawing from it an overhead stream comprising methyl acetate, and/or halogen promoter, a bottoms stream comprising a solution of the first catalyst, and a liquid acetic acid sidestream; and hydrogenating acetic acid of the liquid acetic acid sidestream in the presence of a second catalyst and under conditions effective to form a crude ethanol product comprising ethanol and water. No flashing vessel is used to purify the liquid reaction product. Ethanol is recovered from the crude ethanol product.

Abstract: This invention relates to processes for producing ethanol from at least two different streams obtained by carbonylating methanol. The process comprises the steps of reacting carbon monoxide with at least one reactant in a first reactor containing a reaction medium to produce a reaction solution comprising acetic acid, wherein the at least one reactant is selected from the group consisting of methanol, methyl acetate, methyl formate, dimethyl ether and mixtures thereof and wherein the reaction medium comprises water, acetic acid, methyl iodide, and a first catalyst, purifying the reaction solution to yield an acetic acid product stream and at least one derivative stream, introducing the acetic acid product stream and the at least one derivative stream into a second reactor in the presence of a second catalyst to form a crude ethanol product, and recovering ethanol from the crude ethanol product.

Abstract: In one embodiment, the invention is to a process for forming an ethanol mixture by hydrogenating an acetaldehyde feed stream in the presence of a catalyst. The acetaldehyde feed stream comprises acetaldehyde and at least one of acetic acid and ethanol. Preferably the acetaldehyde feed stream is a by-product stream from a vinyl acetate synthesis process.

Abstract: In one embodiment, the invention is to a process for producing a water stream comprising the steps of hydrogenating acetic acid to form a crude ethanol product and separating at least a portion of the crude ethanol product in at least one column of a plurality of columns into a distillate comprising ethanol and a residue comprising the water stream. The water stream preferably is essentially free of organic impurities other than acetic acid and ethanol.

Abstract: Recovery of an ester feed stream, optionally with the recovery of ethanol, from a crude ethanol product obtained from the hydrogenation of acetic acid. Separation and purification processes of the crude ethanol products are employed to allow recovery of the ester feed stream and for integration of the ester feed stream with an esters production process. The composition of the ester feed stream may vary, but at least comprises ethyl acetate and ethanol. The ester feed stream may be fed to one or more locations within the esters production process depending on the composition of the ester feed stream.

Abstract: Recovery of an ethyl acetate solvent, optionally with the recovery of ethanol, from a crude product obtained from the hydrogenation of acetic acid. Separation and purification processes of the crude product are employed to allow recovery of the ethyl acetate solvent.

Abstract: Purifying and/or recovery of ethanol from a crude ethanol product obtained from the hydrogenation of acetic acid. Separation and purification processes of crude ethanol mixture are employed to allow recovery of ethanol and remove impurities. In addition, the process involves returning acetaldehyde separated from the crude ethanol product to the reactor.

Abstract: A process for reducing ethyl acetate and/or diethyl acetal concentration of a crude ethanol product by hydrolysis is disclosed. A portion of the water is initially separated from the crude ethanol product in a first column residue. Ethyl acetate in the first column distillate is hydrolyzed to form additional ethanol and acetic acid. Product ethanol is recovered in a second distillation column preferably in a side stream and acetic acid is removed in the second column residue.

Abstract: To reduce acetal concentrations when separating ethanol from a crude product in one or more distillation column, at least one of the columns has a stripping section that comprises at least 40 stages to favor hydrolysis of the acetal. The crude product may comprise ethanol, acetaldehyde, water and one or more acetals, such as diethyl acetal. The acetal concentration may be reduced thus reducing the need to separate acetal from the crude product.

Abstract: The present invention relates to the recovery of ethanol from a crude ethanol product obtained from the hydrogenation of acetic acid. Separation and purification processes of crude ethanol product are employed to allow recovery of an anhydrous ethanol composition. The process involves separating the crude ethanol product using one or more extractive distillation columns that employ one or more extractive agents. The anhydrous ethanol composition comprises less than 1 wt. % water, based on the total weight of the anhydrous ethanol composition.

Abstract: Recovery of an alcohol such as ethanol from a crude alcohol product, preferably obtained from the hydrogenation of acetic acid using a low energy process. The crude ethanol product is separated in a column to produce a distillate stream comprising ethyl acetate and a residue stream comprising ethanol, acetic acid, and water. The ethanol product is recovered in a second column as an ethanol side stream.

Abstract: To reduce acetal concentrations when separating ethanol from a crude product in one or more distillation column, at least one of the columns is operated at a higher pressure to increase the equilibrium constant that favors hydrolysis of the acetal. The crude product may comprise ethanol, acetaldehyde, water and one or more acetals, such as diethyl acetal. The acetal concentration may be reduced thus reducing the need to separate acetal from the crude product.

Abstract: A process is described for producing an alcohol product, in which (a) a first feed composition comprising acetic acid is converted to a product comprising acetone; and (b) a second feed composition comprising at least part of the acetone produced in (a) is hydrogenated in the presence of a catalyst to produce a hydrogenation effluent comprising isopropanol.

Abstract: Two or more vapor-liquid separators are used in a process for removing at least one non-condensable gas from a crude alcohol mixture prepared by hydrogenating alkanoic acid and/or esters thereof. The vapor-liquid separators may comprise flashers or knock-out pots and are suitable for removing non-condensable gas, including those gases that are dissolved in the liquid. The multiple vapor-liquid separators may be in series prior to any separation of organic components. In addition, there may be a vapor-liquid separator before and after a distillation column for treating the feed to the column.

Abstract: To reduce acetal and/or ester concentrations when separating ethanol from a crude product in one or more distillation column, at least one of the columns is operated at a higher pressure to increase the equilibrium constant that favors hydrolysis of the acetal. The crude product may comprise ethanol, acetaldehyde, water, ethyl acetate and one or more acetals, such as diethyl acetal. The acetal and/or ester concentration may be reduced thus reducing the need to separate acetal and/or ester from the crude product.

Abstract: To reduce acetal concentrations when separating ethanol from a crude product in one or more distillation column, at least one of the columns is operated at a higher pressure to increase the equilibrium constant that favors hydrolysis of the acetal. The crude product may comprise ethanol, acetaldehyde, water and one or more acetals, such as diethyl acetal. The acetal concentration may be reduced thus reducing the need to separate acetal from the crude product.

Abstract: A process for operating a distillation column to separate an ethanol mixture comprising ethanol and acetic acid where the recovered ethanol comprises less than 700 wppm acetic acid. The operating conditions for the column may vary depending on the fed composition. In particular the process provides energy efficient recovery of ethanol with low concentration acetic acid.

Abstract: In one embodiment, the invention is to a process for purifying a crude ethanol product. The process comprises the step of hydrogenating acetic acid in a first reaction zone in the presence of a first catalyst to form the crude ethanol product comprising ethanol, acetaldehyde, acetic acid, water, and acetal. The process further comprises the step of separating at least a portion of the crude ethanol product into a refined ethanol stream and a by-product stream. The refined ethanol stream comprises ethanol and acetaldehyde; and the by-product stream comprises acetic acid and a substantial portion of the water from the crude ethanol product. The process further comprises the step of hydrolyzing in a second reaction zone at least a portion of the acetal.