The present disclosure relates generally to processes for separating an effluent in an acetic acid production unit. Accordingly, one aspect of the disclosure provides a process including transferring at least a portion of a carbonylation reaction effluent to the bottom section of a tank, evaporating at least a portion of the effluent to form a vapour fraction, spraying a spray liquid onto a porous demister surface of a demister section of the tank, collecting and returning a liquid fraction of the effluent from at least one chimney tray in the tank to a fractionation section or the bottom section of the tank, and withdrawing from a top section of the tank at least a portion of the vapour fraction, the vapour fraction comprising acetic acid, the vapour fraction having been passed from the bottom section through the fractionation section, and then through one or more chimneys of the at least one chimney tray, and then through the spray section, and then through the porous demister surface of the demister section.

The present disclosure relates generally to processes for separating an effluent in an acetic acid production unit. Accordingly, one aspect of the disclosure provides a process including transferring at least a portion of a carbonylation reaction effluent to the bottom section of a tank, evaporating at least a portion of the effluent to form a vapour fraction, spraying a spray liquid onto a porous demister surface of a demister section of the tank, collecting and returning a liquid fraction of the effluent from at least one chimney tray in the tank to a fractionation section or the bottom section of the tank, and withdrawing from a top section of the tank at least a portion of the vapour fraction, the vapour fraction comprising acetic acid, the vapour fraction having been passed from the bottom section through the fractionation section, and then through one or more chimneys of the at least one chimney tray, and then through the spray section, and then through the porous demister surface of the demister section.

The present disclosure relates generally to processes for separating an effluent in an acetic acid production unit. Accordingly, one aspect of the disclosure provides a process including transferring at least a portion of a carbonylation reaction effluent to the bottom section of a tank, evaporating at least a portion of the effluent to form a vapour fraction, spraying a spray liquid onto a porous demister surface of a demister section of the tank, collecting and returning a liquid fraction of the effluent from at least one chimney tray in the tank to a fractionation section or the bottom section of the tank, and withdrawing from a top section of the tank at least a portion of the vapour fraction, the vapour fraction comprising acetic acid, the vapour fraction having been passed from the bottom section through the fractionation section, and then through one or more chimneys of the at least one chimney tray, and then through the spray section, and then through the porous demister surface of the demister section.

A process for the preparation of a saturated aliphatic carboxylic acid with 3 to 5 carbon atoms by oxidation of the corresponding aldehyde with oxygen in which (a) the corresponding aldehyde is converted with oxygen at a temperature of 40 to 150° C. and an oxygen partial pressure of 0.001 to 1 MPa to obtain a mixture containing the saturated aliphatic carboxylic acid and ≤2 mol-% of the corresponding aldehyde with respect to the saturated aliphatic carboxylic acid, (b) the mixture obtained in step (a) is thermally treated in the liquid phase at a temperature of 80 to 250° C. and a pressure of 0.1 to 2 MPa abs for 0.25 to 100 hours, and (c) the mixture obtained in step (b) is distilled in a distillation apparatus to obtain a distillate containing ≥90 wt.-% of the saturated aliphatic carboxylic acid and having an active oxygen content of 0 to 25 wt.-ppm based on the distillate.

A process for the preparation of a saturated aliphatic carboxylic acid with 3 to 5 carbon atoms by oxidation of the corresponding aldehyde with oxygen in which (a) the corresponding aldehyde is converted with oxygen at a temperature of 40 to 150° C. and an oxygen partial pressure of 0.001 to 1 MPa to obtain a mixture containing the saturated aliphatic carboxylic acid and ≤2 mol-% of the corresponding aldehyde with respect to the saturated aliphatic carboxylic acid, (b) the mixture obtained in step (a) is thermally treated in the liquid phase at a temperature of 80 to 250° C. and a pressure of 0.1 to 2 MPa abs for 0.25 to 100 hours, and (c) the mixture obtained in step (b) is distilled in a distillation apparatus to obtain a distillate containing ≥90 wt.-% of the saturated aliphatic carboxylic acid and having an active oxygen content of 0 to 25 wt.-ppm based on the distillate.

A process for the preparation of a saturated aliphatic carboxylic acid with 3 to 5 carbon atoms by oxidation of the corresponding aldehyde with oxygen in which (a) the corresponding aldehyde is converted with oxygen at a temperature of 40 to 150° C. and an oxygen partial pressure of 0.001 to 1 MPa to obtain a mixture containing the saturated aliphatic carboxylic acid and ≤2 mol-% of the corresponding aldehyde with respect to the saturated aliphatic carboxylic acid, (b) the mixture obtained in step (a) is thermally treated in the liquid phase at a temperature of 80 to 250° C. and a pressure of 0.1 to 2 MPa abs for 0.25 to 100 hours, and (c) the mixture obtained in step (b) is distilled in a distillation apparatus to obtain a distillate containing ≥90 wt.-% of the saturated aliphatic carboxylic acid and having an active oxygen content of 0 to 25 wt.-ppm based on the distillate.

A process for separating or removing permanganate reducing compounds (PRC's) from a first mixture containing at least one PRC, methyl iodide, and water comprises the steps of: feeding the first mixture to a feed port of a distillation column, and distilling and separating the first mixture into an upper stream and a lower stream, wherein the distillation of the first mixture forms a second mixture at an upper position than the feed port, and the process further comprises the steps of: withdrawing the second mixture as the upper stream, and withdrawing the lower stream from a lower position than the feed port.

A process for separating or removing permanganate reducing compounds (PRC's) from a first mixture containing at least one PRC, methyl iodide, and water comprises the steps of: feeding the first mixture to a feed port of a distillation column, and distilling and separating the first mixture into an upper stream and a lower stream, wherein the distillation of the first mixture forms a second mixture at an upper position than the feed port, and the process further comprises the steps of: withdrawing the second mixture as the upper stream, and withdrawing the lower stream from a lower position than the feed port.

The present invention relates to a hydrogen gas production method, which includes: a first step of concentrating an aqueous solution containing an alkali metal formate; a second step of protonating at least a part of the alkali metal formate by electrodialysis to produce a formic acid; and a third step of decomposing the formic acid to produce a hydrogen gas.

The present invention relates to a hydrogen gas production method, which includes: a first step of concentrating an aqueous solution containing an alkali metal formate; a second step of protonating at least a part of the alkali metal formate by electrodialysis to produce a formic acid; and a third step of decomposing the formic acid to produce a hydrogen gas.