Provided is a process for producing acrylic acid, wherein the process comprises a first step and a second step in which a first absorbent is added to a reaction product of a bio-material and cooled to separate a first low-boiling-point material including acetaldehyde (ACHO) and a first high-boiling-point material including acrylic acid (AA). The process is capable of producing high-purity acrylic acid at high yield, and acetaldehyde is produced as by-product along with the reaction product of the bio-material. The process includes separating the acetaldehyde produced as by-product into a high-purity product at high yield.

Provided is a process for producing acrylic acid, wherein the process comprises a first step and a second step in which a first absorbent is added to a reaction product of a bio-material and cooled to separate a first low-boiling-point material including acetaldehyde (ACHO) and a first high-boiling-point material including acrylic acid (AA). The process is capable of producing high-purity acrylic acid at high yield, and acetaldehyde is produced as by-product along with the reaction product of the bio-material. The process includes separating the acetaldehyde produced as by-product into a high-purity product at high yield.

Provided is a process for producing acrylic acid, comprising (step 1) separating a first low-boiling-point material including acetaldehyde (ACHO) and a first high-boiling-point material including acrylic acid (AA) by adding a first absorbent to a reaction product of a bio-raw material and cooling the result; (step 2) separating a first incompressible material and a second low-boiling-point material including acetaldehyde (ACHO) by adding a second absorbent to the first low-boiling-point material including acetaldehyde (ACHO) and cooling the result; (step 3) heating the second low-boiling-point material including acetaldehyde (ACHO); (step 4) separating the heated second low-boiling-point material including acetaldehyde (ACHO) to acetaldehyde (ACHO) and the second absorbent and (step 5) producing acrylic acid by purifying the first high-boiling-point material including acrylic acid (AA).

Provided is a process for producing acrylic acid, comprising (step 1) separating a first low-boiling-point material including acetaldehyde (ACHO) and a first high-boiling-point material including acrylic acid (AA) by adding a first absorbent to a reaction product of a bio-raw material and cooling the result; (step 2) separating a first incompressible material and a second low-boiling-point material including acetaldehyde (ACHO) by adding a second absorbent to the first low-boiling-point material including acetaldehyde (ACHO) and cooling the result; (step 3) heating the second low-boiling-point material including acetaldehyde (ACHO); (step 4) separating the heated second low-boiling-point material including acetaldehyde (ACHO) to acetaldehyde (ACHO) and the second absorbent and (step 5) producing acrylic acid by purifying the first high-boiling-point material including acrylic acid (AA).

Provided is a process for producing acrylic acid, comprising (step 1) separating a first low-boiling-point material including acetaldehyde (ACHO) and a first high-boiling-point material including acrylic acid (AA) by adding a first absorbent to a reaction product of a bio-raw material and cooling the result; (step 2) separating a first incompressible material and a second low-boiling-point material including acetaldehyde (ACHO) by adding a second absorbent to the first low-boiling-point material including acetaldehyde (ACHO) and cooling the result; (step 3) heating the second low-boiling-point material including acetaldehyde (ACHO); (step 4) separating the heated second low-boiling-point material including acetaldehyde (ACHO) to acetaldehyde (ACHO) and the second absorbent and (step 5) producing acrylic acid by purifying the first high-boiling-point material including acrylic acid (AA).

The invention relates to a process for obtaining a formate from a reaction mixture (10) in which a polyoxometallate ion, which acts as a catalyst, is in contact with an organic material at a temperature below 120° C. to produce formic acid in an aqueous solution, with the following steps. a) separating a mixture of formic acid and water from the reaction mixture by reverse osmosis and/or as vapor (18), the vapor (18) subsequently being condensed, and b) reacting the formic acid with a hydroxide (24) in aqueous solution to produce a solution of a formate.

The invention relates to a process for obtaining a formate from a reaction mixture (10) in which a polyoxometallate ion, which acts as a catalyst, is in contact with an organic material at a temperature below 120° C. to produce formic acid in an aqueous solution, with the following steps. a) separating a mixture of formic acid and water from the reaction mixture by reverse osmosis and/or as vapor (18), the vapor (18) subsequently being condensed, and b) reacting the formic acid with a hydroxide (24) in aqueous solution to produce a solution of a formate.

Provided is an acetic acid production method including an absorption step that enables efficient and energy-saving separation of methyl iodide in a downstream step, when provided, of separating methyl iodide from a solution after the absorption of methyl iodide. The acetic acid production method according to the present invention includes an absorption step in an acetic acid production process. In the absorption step, at least a portion of offgases formed in the process is fed to an absorption column, is brought into contact with an absorbent including an organic acid having a higher boiling point as compared with acetic acid to allow the absorbent to absorb an iodine compound from the offgas, and a gas having a lower iodine compound concentration as compared with the offgas, and a solution containing the absorbent and the iodine compound are thereby to be separated.

Provided is an acetic acid production method including an absorption step that enables efficient and energy-saving separation of methyl iodide in a downstream step, when provided, of separating methyl iodide from a solution after the absorption of methyl iodide. The acetic acid production method according to the present invention includes an absorption step in an acetic acid production process. In the absorption step, at least a portion of offgases formed in the process is fed to an absorption column, is brought into contact with an absorbent including an organic acid having a higher boiling point as compared with acetic acid to allow the absorbent to absorb an iodine compound from the offgas, and a gas having a lower iodine compound concentration as compared with the offgas, and a solution containing the absorbent and the iodine compound are thereby to be separated.

Provided is an acetic acid production method including an absorption step that enables efficient and energy-saving separation of methyl iodide in a downstream step, when provided, of separating methyl iodide from a solution after the absorption of methyl iodide. The acetic acid production method according to the present invention includes an absorption step in an acetic acid production process. In the absorption step, at least a portion of offgases formed in the process is fed to an absorption column, is brought into contact with an absorbent including an organic acid having a higher boiling point as compared with acetic acid to allow the absorbent to absorb an iodine compound from the offgas, and a gas having a lower iodine compound concentration as compared with the offgas, and a solution containing the absorbent and the iodine compound are thereby to be separated.