The present invention relates to a process for treating aqueous effluents containing formaldehyde by distillation in the presence of acetic acid, in particular to a process for treating aqueous solutions resulting from the synthesis of acrylic acid. The invention also relates to the use of the purified aqueous solution in a process for producing acrylic acid by catalytic oxidation of propylene and/or propane in steam dilution.

The present invention relates to a process for treating aqueous effluents containing formaldehyde by distillation in the presence of acetic acid, in particular to a process for treating aqueous solutions resulting from the synthesis of acrylic acid. The invention also relates to the use of the purified aqueous solution in a process for producing acrylic acid by catalytic oxidation of propylene and/or propane in steam dilution.

The present invention relates to a process for treating aqueous effluents containing formaldehyde by distillation in the presence of acetic acid, in particular to a process for treating aqueous solutions resulting from the synthesis of acrylic acid. The invention also relates to the use of the purified aqueous solution in a process for producing acrylic acid by catalytic oxidation of propylene and/or propane in steam dilution.

Disclosed is a method for removing acetaldehyde and other permanganate reducing compounds (PRCs) from a process stream in the methanol carbonylation process for making acetic acid. The method includes the steps of forming an azeotrope to reduce the boiling point of the acetaldehyde and other PRCs to facilitate separation of the acetaldehyde and other PRCs from the process. In one embodiment the azeotrope comprises butane and acetaldehyde.

Disclosed is a method for removing acetaldehyde and other permanganate reducing compounds (PRCs) from a process stream in the methanol carbonylation process for making acetic acid. The method includes the steps of forming an azeotrope to reduce the boiling point of the acetaldehyde and other PRCs to facilitate separation of the acetaldehyde and other PRCs from the process. In one embodiment the azeotrope comprises butane and acetaldehyde.

A system and method for removing acetaldehyde from an acetic acid system, including providing a solution from the acetic acid system, the stream having methyl iodide and acetaldehyde, distilling the solution to produce an overhead stream having a higher concentration of acetaldehyde, contacting the overhead stream, and optionally a hydroxyl compound, with an acid catalyst to convert the acetaldehyde to an aldehyde derivative having a higher boiling point than acetaldehyde.

A system and method for removing acetaldehyde from an acetic acid system, including providing a solution from the acetic acid system, the stream having methyl iodide and acetaldehyde, distilling the solution to produce an overhead stream having a higher concentration of acetaldehyde, contacting the overhead stream, and optionally a hydroxyl compound, with an acid catalyst to convert the acetaldehyde to an aldehyde derivative having a higher boiling point than acetaldehyde.

The present disclosure relates to a process for producing high-purity acrylic acid using a dividing wall distillation column and in some instances using water as an entrainer and azeotroping agent. This disclosure provides a process for separating acrylic acid from recovered feed streams which comprise saturated organic acids including propionic acid. The resulting acrylic acid product is of sufficient purity to produce acrylate esters and high molecular weight acrylic acid polymers.

The present disclosure relates to a process for producing high-purity acrylic acid using a dividing wall distillation column and in some instances using water as an entrainer and azeotroping agent. This disclosure provides a process for separating acrylic acid from recovered feed streams which comprise saturated organic acids including propionic acid. The resulting acrylic acid product is of sufficient purity to produce acrylate esters and high molecular weight acrylic acid polymers.

The present disclosure provides azeotrope or azeotrope-like compositions including trifluoroiodomethane (CF.sub.3I) and trifluoroacetyl chloride (CF.sub.3COCl), and a method of forming an azeotrope or azeotrope-like composition comprising the step of combining trifluoroacetyl chloride (CF.sub.3COCl) and trifluoroiodomethane (CF.sub.3I) to form an azeotrope or azeotrope-like composition.