Abstract: A process for producing acetic acid is disclosed in which the water concentration is controlled in the side stream between two columns. Controlling the water concentration by the liquid light phase recycle controls the hydrogen iodide concentration in the side stream to be less than or equal to 50 wppm.

Abstract: A process for producing an acetic acid product having low butyl acetate content via a carbonylation reaction. The carbonylation reaction is carried out at a temperature from 100 to 300° C., a hydrogen partial pressure from 0.3 to 2 atm, and a metal catalyst concentration from 100 to 3000 wppm, based on the weight of the reaction medium. The butyl acetate concentration in the acetic acid product may be controlled by removing acetaldehyde from a stream derived from the reaction medium and/or by adjusting at least one of reaction temperature, hydrogen partial pressure, and metal catalyst concentration.

Abstract: A process for producing acetic acid is disclosed, in which the methyl iodide concentration is maintained in the vapor product stream formed in a flashing step. The process includes introducing a lithium compound into the reactor and maintaining a concentration of lithium acetate in the reaction medium is in an amount from 0.3 to 0.7 wt. %. The reaction medium is fed forward to the flashing step. The methyl iodide concentration in the vapor product stream ranges from 24 to less than 36 wt. %, based on the weight of the vapor product stream. The vapor product stream is distilled in a first column to obtain an acetic acid product stream comprising acetic acid and hydrogen iodide in an amount of less than or equal to 300 wppm and/or methyl iodide in an amount from 0.1 to 6 wt. %.

Abstract: A process for producing acetic acid comprising the steps of carbonylating methanol in a reaction medium to form a crude acetic acid product; conveying the crude acetic acid product to a flash vessel at a flash flow rate; flashing the crude acetic acid product to form a first vapor stream comprising acetic acid and a liquid residue stream comprising metal catalyst and halide salt; separating the flashed vapor stream to form a second vapor stream comprising methyl iodide a sidedraw comprising purified acetic acid and water, and a liquid residue stream. The process further comprises the steps of condensing at least a portion of the second vapor stream to form at least one liquid phase and refluxing to the light ends column at least a portion of the at least one liquid phase at a reflux rate. The reflux rate is adjusted based on changes in the flash flow rate.

Abstract: A process for producing high purity acetic acid from a carbonylation reaction, wherein the carbonylation reaction is carried out while maintaining a low ethyl iodide content in the reaction medium. The ethyl iodide concentration may be maintained by removing acetaldehyde from the reaction medium and/or by adjusting at least one A) hydrogen partial pressure in the reactor, B) methyl acetate concentration of the reaction medium; and/or C) methyl iodide concentration of the reaction medium.

Abstract: Processes for producing acetic acid wherein at least one process vent stream is treated in an absorber column that utilizes a scrubber solvent, e.g., acetic acid, methanol, and/or methyl acetate to remove hydrogen iodide therefrom.

Abstract: In a process for improving a carbonylation process, iron is removed to maintain an effective Space Time Yield (STY) of the rhodium catalyst of at least 80% of the maximum STY. The process comprises carbonylating methanol in a reactor in a reaction medium comprising water, a rhodium catalyst, methyl iodide and a halide salt, separating a portion of the reaction medium in a flash vessel to form a less volatile stream and a vapor product stream comprising acetic acid, recycling a liquid stream to the reactor, wherein the liquid stream comprises a portion of the less volatile stream and wherein the liquid stream comprises iron, and removing a portion of the iron from the liquid stream to maintain an effective STY of the rhodium catalyst of at least 80% of the maximum STY.

Abstract: A process for producing an acetic acid product having low butyl acetate content via a carbonylation reaction. The carbonylation reaction is carried out at a temperature from 100 to 300° C., a hydrogen partial pressure from 0.3 to 2 atm, and a rhodium catalyst concentration from 100 to 3000 wppm, based on the weight of the reaction medium. The butyl acetate concentration in the acetic acid product may be controlled by removing acetaldehyde from a stream derived from the reaction medium and/or by adjusting at least one of reaction temperature, hydrogen partial pressure, and metal catalyst concentration.

Abstract: A process for producing acetic acid is disclosed, in which the methyl iodide concentration is maintained in the vapor product stream formed in a flashing step. The process includes introducing a lithium compound into the reactor and maintaining a concentration of lithium acetate in the reaction medium is in an amount from 0.3 to 0.7 wt. %. The reaction medium is fed forward to the flashing step. The methyl iodide concentration in the vapor product stream ranges from 24 to less than 36 wt. %, based on the weight of the vapor product stream. The vapor product stream is distilled in a first column to obtain an acetic acid product stream comprising acetic acid and hydrogen iodide in an amount of less than or equal to 300 wppm and/or methyl iodide in an amount from 0.1 to 6 wt. %.

Abstract: Process for producing acetic acid is disclosed in which a lithium compound is added to the reaction medium to maintain a concentration of lithium acetate from 0.3 to 0.7 wt. %. The concentration of the rhodium catalyst is maintained from 300 to 3000 wppm in the reaction medium, the concentration of water is maintained from 0.1 to 4.1 wt. % in the reaction medium, and the concentration of methyl acetate is maintained from 0.6 to 4.1 wt. % in the reaction medium.

Abstract: A process for producing acetic acid is disclosed in which the methyl iodide concentration is maintained in the vapor product stream formed in a flashing step. The methyl iodide concentration in the vapor product stream ranges from 24 to less than 36 wt. % methyl iodide, based on the weight of the vapor product stream. In addition, the acetaldehyde concentration is maintained within the range from 0.005 to 1 wt. % in the vapor product stream. The vapor product stream is distilled in a first column to obtain an acetic acid product stream comprising acetic acid and up to 300 wppm hydrogen iodide and/or from 0.1 to 6 wt. % methyl iodide and an overhead stream comprising methyl iodide, water and methyl acetate.

Abstract: A process for producing acetic acid is disclosed in which the water concentration is controlled in the side stream between two columns. Controlling the water concentration by a recycle rate of the light liquid phase maintains the hydrogen iodide concentration in the side stream to be up to 50 wppm.

Abstract: A process for producing an acetic acid product having low butyl acetate content via a carbonylation reaction. The carbonylation reaction is carried out at a temperature from 100 to 300° C., a hydrogen partial pressure from 0.3 to 2 atm, and a metal catalyst concentration from 100 to 3000 wppm, based on the weight of the reaction medium. The butyl acetate concentration in the acetic acid product may be controlled by removing acetaldehyde from a stream derived from the reaction medium and/or by adjusting at least one of reaction temperature, hydrogen partial pressure, and metal catalyst concentration.

Abstract: Processes for producing acetic acid wherein at least one process vent stream is treated in an absorber column that utilizes multiple scrubber solvents, e.g., a first absorbent comprising acetic acid and a second absorbent comprising methanol and/or methyl acetate.

Abstract: Processes for the reduction and/or removal of permanganate reducing compounds (PRC'S) formed by the carbonylation of methanol in the presence of a Group VIII metal carbonylation catalyst to produce acetic acid are disclosed. More specifically, processes for reducing and/or removing PRC's or their precursors from intermediate streams during the formation of acetic acid by said carbonylation processes are disclosed. In particular, processes in which a low boiling overhead vapor stream from a light ends column is subjected to a distillation to obtain an overhead that is subjected to an extraction to selectively remove and/or reduce PRC's from the process is disclosed. The processes include steps of recycling one or more return streams derived from the distillation step and/or the extraction step to a light ends column and/or a drying column in order to improve water control in the overall reaction system.

Abstract: A method for stabilizing a carbonylation catalyst with carbon monoxide recovered from a gaseous stream derived from a carbonylation reaction. The carbon monoxide enriched stream is fed downstream of the carbonylation reactor, preferably to a flasher or light ends column, to enhance catalyst stability throughout the process.

Abstract: Processes for the reduction and/or removal of permanganate reducing compounds (PRC'S) formed by the carbonylation of methanol in the presence of a Group VIII metal carbonylation catalyst to produce acetic acid are disclosed. More specifically, processes for reducing and/or removing PRC's or their precursors from intermediate streams during the formation of acetic acid by said carbonylation processes are disclosed. In particular, processes in which a low boiling overhead vapor stream from a light ends column is subjected to a distillation to obtain an overhead that is subjected to an extraction to selectively remove and/or reduce PRC's from the process is disclosed. The processes include steps of recycling one or more return streams derived from the distillation step and/or the extraction step to a light ends column and/or a drying column in order to improve water control in the overall reaction system.

Abstract: Ethanol production processes using a mixed feed comprising from 20 to 95 wt. % acetic acid, from 5 to 80 wt. % acetic anhydride, and from 0 to 20 wt. % esters selected from the group consisting of methyl acetate, ethyl acetate, or mixtures thereof are disclosed herein. The process comprises contacting the mixed feed with hydrogen in the vapor phase in a reactor in the presence of a catalyst comprising tin, cobalt, platinum, and combinations thereof to form a crude ethanol product having an ethanol to water molar ratio of greater than 1 and separating the crude ethanol product in one or more distillation columns to yield an ethyl acetate stream and an ethanol stream. The process may be integrated with an acetic anhydride production process to obtain further economic savings.

Abstract: Processes for contacting an olefin feed stream, preferably comprising ethylene, with at least one stream from an ethanol production process that comprises water. The hydration reaction produces ethanol to improve overall ethanol yields from the hydrogenation acetic acid and esters thereof.

Abstract: Processes for the reduction and/or removal of permanganate reducing compounds (PRC'S) formed by the carbonylation of methanol in the presence of a Group VIII metal carbonylation catalyst to produce acetic acid are disclosed. More specifically, processes for reducing and/or removing PRC's or their precursors from intermediate streams during the formation of acetic acid by said carbonylation processes are disclosed. In particular, processes in which a low boiling overhead vapor stream from a light ends column is subjected to a distillation to obtain an overhead that is subjected to an extraction to selectively remove and/or reduce PRC's from the process is disclosed. The processes include steps of recycling one or more return streams derived from the distillation step and/or the extraction step to a light ends column and/or a drying column in order to improve water control in the overall reaction system.