METHOD FOR PRODUCING ACRYLIC ACID FROM METHANOL AND ACETIC ACID Russian patent published in 2017 - IPC C07C45/38 C07C47/04 C07C51/353 C07C47/52 C07C57/04 C07C57/07 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing acrylic acid from methanol and acetic acid, which involves following operations: through a first reaction zone A, which is loaded at least one oxidation catalyst A, passing a stream of reaction gas mixture A, containing reagents – methanol and molecular oxygen, as well as at least one inert gas diluent, different from water vapour, and when passing said reaction zone A methanol contained in supplied reaction gas mixture A, in conditions of heterogeneous catalysis is oxidised to formaldehyde and water vapour, so as to form a gaseous mixture of products A, containing formaldehyde, water vapour, at least one inert gas diluent, differing from water vapour, and optionally, excess molecular oxygen, and stream of gaseous mixture of products A exits reaction zone A, wherein to reaction gas mixture A passing through reaction zone A, on its path through reaction zone A can optionally be supplied additional molecular oxygen and/or additional inert gas diluent, optionally a stream of gaseous mixture of products A, leaving reaction zone A, is fed into separation zone T*, and in said separation zone T* from gaseous mixture of products A is optionally separated unreacted methanol still contained in gaseous mixture of products A, wherein remains gaseous mixture of products A*, containing formaldehyde, and a stream of gaseous mixture of products A* exits reaction zone A, from stream of gaseous mixture of products A or from stream of gaseous mixture of products A*, as well as at least one other stream of substances containing acetic acid, is obtained a stream of incoming reaction gas mixture B containing acetic acid, water vapour, at least one inert gas diluent, different from water vapour, formaldehyde and optionally molecular oxygen, in which is contained molar amount of acetic acid n_HAc greater than molar amount of formaldehyde n_Fd contained therein, through second reaction zone B, in which is loaded at least one catalyst for aldol condensation B, is passed a stream of incoming reaction gas mixture B, and when passing said reaction zone B formaldehyde contained in supplied reaction gas mixture B, together with acetic acid contained in supplied reaction gas mixture B, under conditions of heterogeneous catalysis is condensed to acrylic acid and H₂O, to form a gaseous mixture of products B containing acrylic acid, acetic acid, water vapour, at least one inert gas diluent, different from water vapour, and optionally molecular oxygen, and a stream of gaseous mixture of products B comes out of reaction zone B, wherein to reaction gas mixture B passing through reaction zone B, on its path through reaction zone B, may be supplied additional molecular oxygen and/or additional inert gas diluent, stream of gaseous mixture of products B, leaving reaction zone B is fed into separation zone T, and in said separation zone T is divided at least into three streams substances – X, Y and Z, wherein stream of acrylic acid contained in stream of substances X, is greater than stream of acrylic acid contained in streams of substances Y and Z, taken together, stream of acetic acid contained in stream of substances Y is greater than streams of acetic acid contained in streams of substances X and Z, taken together, stream of inert gas diluent, different from water vapour, contained in stream of substance Z, is greater than streams of inert gas diluent, different from water vapour contained in streams of substances X and Y taken together, and stream of substance Y is returned into reaction zone B and is additionally used for producing incoming reaction gas mixture B.

EFFECT: disclosed is a method of producing acrylic acid from methanol and acetic acid.

21 cl