Abstract: The invention provides systems and processes for concentrating acetic acid and acetic anhydride streams. The systems allow operation of equipment used for such concentrations in two or more modes of operation. At least one mode is intended to produce a concentrated or purified acetic acid stream. At least one other mode is intended to produce a concentrated or purified acetic anhydride stream.

Abstract: The invention provides processes for purification of streams containing carboxylic acids and carboxylic acid anhydrides without using the amount of high-cost, corrosion resistant alloy required for a distillation column. The invention provides methods in which streams containing carboxylic acids and carboxylic acid anhydrides are subjected to a hydrolysis process by combining them with a stoichiometric excess of water and optionally an added hydrolysis catalyst. The resulting hydrolyzed stream is subsequently separated to produce a stream containing carboxylic acid and water and a carboxylic acid product stream comprising carboxylic acid.

Abstract: Disclosed is a process for the coproduction of acetic acid and acetic anhydride by producing in a first carbonylation reactor a carbonylation product mixture containing acetic anhydride, removing the carbonylation mixture from the first carbonylation reactor, contacting the carbonylation mixture with methanol to react with and convert some or all of the acetic anhydride contained in the mixture to acetic acid and methyl acetate, feeding the resulting reaction composition to a second carbonylation reactor and contacting the reaction composition to carbonylation.

Abstract: The invention provides systems and processes for concentrating acetic acid and acetic anhydride streams. The systems allow operation of equipment used for such concentrations in two or more modes of operation. At least one mode is intended to produce a concentrated or purified acetic acid stream. At least one other mode is intended to produce a concentrated or purified acetic anhydride stream.

Abstract: The invention provides processes for purification of streams containing carboxylic acids and carboxylic acid anhydrides without using the amount of high-cost, corrosion resistant alloy required for a distillation column. The invention provides methods in which streams containing carboxylic acids and carboxylic acid anhydrides are subjected to a hydrolysis process by combining them with a stoichiometric excess of water and optionally an added hydrolysis catalyst. The resulting hydrolyzed stream is subsequently separated to produce a stream containing carboxylic acid and water and a carboxylic acid product stream comprising carboxylic acid.

Abstract: Disclosed is a process for the coproduction of acetic acid and acetic anhydride by producing in a first carbonylation reactor a carbonylation product mixture containing acetic anhydride, removing the carbonylation mixture from the first carbonylation reactor, contacting the carbonylation mixture with methanol to react with and convert some or all of the acetic anhydride contained in the mixture to acetic acid and methyl acetate, feeding the resulting reaction composition to a second carbonylation reactor and contacting the reaction composition to carbonylation.

Abstract: Disclosed is a process for the production of acetic acid or mixtures of acetic acid and acetic anhydride in a carbonylation process wherein a mixture comprising methyl acetate and/or dimethyl ether and methyl iodide is contacting in the liquid phase with carbon monoxide in the presence of a carbonylation catalyst at elevated pressures and temperatures. Methanol, water, or a mixture thereof is added to an acetic anhydride-containing stream within a flash evaporation zone to convert some or all of the acetic anhydride to acetic acid and optionally methyl acetate and to provide heat for the evaporation of a portion of the product effluent produced by the carbonylation process.

Abstract: Disclosed is a process for the production of acetic acid or mixtures of acetic acid and acetic anhydride in a carbonylation process wherein a mixture comprising methyl acetate and/or dimethyl ether and methyl iodide is contacting in the liquid phase with carbon monoxide in the presence of a carbonylation catalyst at elevated pressures and temperatures. Methanol, water, or a mixture thereof is added to an acetic anhydride-containing stream within a flash evaporation zone to convert some or all of the acetic anhydride to acetic acid and optionally methyl acetate and to provide heat for the evaporation of a portion of the product effluent produced by the carbonylation process.