Acetic acid is manufactured by a method of carbonylating raw material with carbon monoxide, the method comprising: a reaction step of forming a reaction mixture containing acetic acid inside a reactor; and a purification step of purifying the reaction mixture to thereby obtain product acetic acid. The purification step includes: a flash evaporation step of separating the reaction mixture into a vapor-phase mixture and a liquid-phase mixture; a first distillation step of distilling the vapor-phase mixture to thereby separate and remove low-boiling point components and obtain crude acetic acid; and a second distillation step of introducing the crude acetic acid into a heavy ends column and distilling the crude acetic acid to thereby purify the crude acetic acid and obtain product acetic acid. In the second distillation step, the low-boiling point components remaining in the crude acetic acid are drawn out from a column top of the heavy ends column.

The present invention discloses a method for directly constructing highly optically active tetrasubstituted allenic acid compounds, i.e., a one-step process for directly constructing highly optically active axially chiral tetrasubstituted allenic acid compounds by using tertiary propargyl alcohol, carbon monoxide and water as reactants in an organic solvent in the presence of palladium catalyst, chiral diphosphine ligand, monophosphine ligand and organic phosphoric acid. The method of the present invention has the following advantages: operations are simple, raw materials and reagents are readily available, the reaction conditions are mild, the substrate has high universality, the functional group has good compatibility, and the reaction has high enantioselectivity (90%˜>99% ee). The highly optically active allenic acid compounds obtained by the present invention can be used as an important intermediate to construct γ-butyrolactone compounds containing tetrasubstituted chiral quaternary carbon centers, tetrasubstituted allenic alcohol and other compounds.

The present invention discloses a method for directly constructing highly optically active tetrasubstituted allenic acid compounds, i.e., a one-step process for directly constructing highly optically active axially chiral tetrasubstituted allenic acid compounds by using tertiary propargyl alcohol, carbon monoxide and water as reactants in an organic solvent in the presence of palladium catalyst, chiral diphosphine ligand, monophosphine ligand and organic phosphoric acid. The method of the present invention has the following advantages: operations are simple, raw materials and reagents are readily available, the reaction conditions are mild, the substrate has high universality, the functional group has good compatibility, and the reaction has high enantioselectivity (90%˜>99% ee). The highly optically active allenic acid compounds obtained by the present invention can be used as an important intermediate to construct γ-butyrolactone compounds containing tetrasubstituted chiral quaternary carbon centers, tetrasubstituted allenic alcohol and other compounds.

Methods and systems for the production of one or more products from a gas stream produced in a methanol production process. The method comprises converting at least a portion of a methane feedstock to a substrate comprising CO and H2. The substrate comprising CO and H2 is anaerobically fermented in a bioreactor to produce one or more alcohols. The method and system may further include process for the production of methanol processes for the production of acetic acid.

Methods and systems for the production of one or more products from a gas stream produced in a methanol production process. The method comprises converting at least a portion of a methane feedstock to a substrate comprising CO and H2. The substrate comprising CO and H2 is anaerobically fermented in a bioreactor to produce one or more alcohols. The method and system may further include process for the production of methanol processes for the production of acetic acid.

Methods and systems for the production of one or more products from a gas stream produced in a methanol production process. The method comprises converting at least a portion of a methane feedstock to a substrate comprising CO and H2. The substrate comprising CO and H2 is anaerobically fermented in a bioreactor to produce one or more alcohols. The method and system may further include process for the production of methanol processes for the production of acetic acid.

This process relates to controlling acetal formation when removing acetaldehyde from a methanol carbonylation process using an extractive distillation column. Acetals may be formed by a secondary reaction of acetaldehyde and an alcohol (such as methanol). The process controls the formations to prevent excess acetal accumulation in the lower stream from the extractive distillation column.

This process relates to controlling acetal formation when removing acetaldehyde from a methanol carbonylation process using an extractive distillation column. Acetals may be formed by a secondary reaction of acetaldehyde and an alcohol (such as methanol). The process controls the formations to prevent excess acetal accumulation in the lower stream from the extractive distillation column.

This process relates to controlling acetal formation when removing acetaldehyde from a methanol carbonylation process using an extractive distillation column. Acetals may be formed by a secondary reaction of acetaldehyde and an alcohol (such as methanol). The process controls the formations to prevent excess acetal accumulation in the lower stream from the extractive distillation column.

Provided herein is a process for the production and purification of acetic acid. In particular, this disclosure relates to improved processes for producing and purifying acetic acid by the carbonylation of methanol in the presence of a Group VIII metal carbonylation catalyst. The acetic acid production and purification process described herein controls the formation and mass composition of acetal impurities, such as 1,1-dimethoxyethane.