The invention relates to a process to separate formic acid from methyltetrahydrofuran (MTHF) said process comprising subjecting a composition comprising formic acid and MTHF to distillation, characterized in that the process comprises adding water to said distillation. This allows for cost-efficient recovery and recycling of MTHF, for example in process to produce and recover formic acid from a biomass hydrolysate.

Disclosed is the integration of the production of acetic anhydride from ketene, and the acetylation of wood using acetylation fluid comprising acetic acid and acetic anhydride. The invention involves combining acetic acid obtained from distillation of acetylation fluid with a residual aqueous acetic acid stream as obtained from ketene production.

Disclosed is the integration of the production of acetic anhydride from ketene, and the acetylation of wood using acetylation fluid comprising acetic acid and acetic anhydride. The invention involves combining acetic acid obtained from distillation of acetylation fluid with a residual aqueous acetic acid stream as obtained from ketene production.

The present invention relates to a method of recovering (meth)acrylic acid and an apparatus used for the recovery method. The recovery method according to the present invention discharges each (meth)acrylic acid aqueous solution of different concentrations at a (meth)acrylic acid absorption tower, and uses an extraction solvent of a specific ratio in the step of extracting (meth)acrylic acid, thus enabling the operation of a continuous process of recovering (meth)acrylic acid that can secure a high (meth)acrylic acid recovery rate, and can simultaneously significantly reduce purification energy cost.

The present invention relates to a method of recovering (meth)acrylic acid and an apparatus used for the recovery method. The recovery method according to the present invention discharges each (meth)acrylic acid aqueous solution of different concentrations at a (meth)acrylic acid absorption tower, and uses an extraction solvent of a specific ratio in the step of extracting (meth)acrylic acid, thus enabling the operation of a continuous process of recovering (meth)acrylic acid that can secure a high (meth)acrylic acid recovery rate, and can simultaneously significantly reduce purification energy cost.

The present invention relates to a method of recovering (meth)acrylic acid and an apparatus used for the recovery method. The recovery method according to the present invention discharges each (meth)acrylic acid aqueous solution of different concentrations at a (meth)acrylic acid absorption tower, and uses an extraction solvent of a specific ratio in the step of extracting (meth)acrylic acid, thus enabling the operation of a continuous process of recovering (meth)acrylic acid that can secure a high (meth)acrylic acid recovery rate, and can simultaneously significantly reduce purification energy cost.

There is disclosed a process for the separation of long chain amino acid and long chain dibasic acid, comprising: (1) recovering alkylamine from an aqueous solution of an alkali hydroxide hydrolysis of the mixed amide derivatives by distilling or by extracting with an extractant solvent; (2) cooling the aqueous solution of step (1) to precipitate a mixed alkali salts of long chain amino acid and dibasic acid; (3) recovering the mixed alkali salts of long chain amino acid and dibasic acid to provide a mother liquor; (4) separating long chain amino acid and dibasic acid by acidification-extraction of long chain dibasic acid with an extractant solvent or by selective dissolution of alkali salt of long chain amino acid in an aqueous solvent; and (4) adding an acid to the mother liquor of step (3) to obtain alkanoic acid.

There is disclosed a process for the separation of long chain amino acid and long chain dibasic acid, comprising: (1) recovering alkylamine from an aqueous solution of an alkali hydroxide hydrolysis of the mixed amide derivatives by distilling or by extracting with an extractant solvent; (2) cooling the aqueous solution of step (1) to precipitate a mixed alkali salts of long chain amino acid and dibasic acid; (3) recovering the mixed alkali salts of long chain amino acid and dibasic acid to provide a mother liquor; (4) separating long chain amino acid and dibasic acid by acidification-extraction of long chain dibasic acid with an extractant solvent or by selective dissolution of alkali salt of long chain amino acid in an aqueous solvent; and (4) adding an acid to the mother liquor of step (3) to obtain alkanoic acid.

There is disclosed a process for the separation of long chain amino acid and long chain dibasic acid, comprising: (1) recovering alkylamine from an aqueous solution of an alkali hydroxide hydrolysis of the mixed amide derivatives by distilling or by extracting with an extractant solvent; (2) cooling the aqueous solution of step (1) to precipitate a mixed alkali salts of long chain amino acid and dibasic acid; (3) recovering the mixed alkali salts of long chain amino acid and dibasic acid to provide a mother liquor; (4) separating long chain amino acid and dibasic acid by acidification-extraction of long chain dibasic acid with an extractant solvent or by selective dissolution of alkali salt of long chain amino acid in an aqueous solvent; and (4) adding an acid to the mother liquor of step (3) to obtain alkanoic acid.

There is disclosed a process for the separation of long chain amino acid and long chain dibasic acid, comprising: (1) cooling the hydrolysis solution to crystallize and separate alkali salt of long chain dibasic acid to provide an aqueous solvent solution; (2) distilling the aqueous solvent solution of step (1) to recover the solvent and to recover alkylamine; (3) cooling the residual solution of step (2) to precipitate and separate alkali salt of long chain amino acid to provide a mother liquor; (4) adding an acid to the mother liquor of step (3) to yield alkanoic acid; (5) adding an acid to an aqueous solution of the alkali salt of long chain dibasic acid of step (1) to obtain long chain dibasic acid; and (6) neutralizing the alkali salt of long chain amino acid of step (3) with an acid to obtain long chain amino acid.