摘要 |
FIELD: chemistry.SUBSTANCE: invention relates to compositions of crude and glacial acrylic acid having a bio-based content greater than about 3 %, used to make polyacrylic acid, particularly, they are produced by the steps comprising: a. providing an aqueous solution of acrylic acid comprising: 1) acrylic acid; and 2) lactic acid, lactic acid derivatives, or mixtures thereof, and wherein said aqueous solution of acrylic acid is essentially free of maleic anhydride, furfural, and formic acid; b. extracting said aqueous solution of acrylic acid, with a solvent to produce an extract; c. drying said extract to produce a dried extract; d. distilling said dried extract to produce distilled acrylic acid composition; e. cooling said distilled acrylic acid composition to a temperature from about -21 °C to about 14 °C to produce crystals of acrylic acid; f. partially melting said crystals of acrylic acid to produce a liquid / solid mixture; g. decanting said liquid / solid mixture to produce a purified acrylic acid solid composition; h. fully melting said purified acrylic acid solid composition to produce a purified acrylic acid liquid composition; and i. determining the acrylic acid purity of said purified acrylic acid liquid composition, and if the purity is less than about 98 wt% acrylic acid, repeating said cooling, partially melting, decanting, and fully melting steps on the purified acrylic acid liquid composition until a purity of about 98 wt% acrylic acid is achieved and said glacial acrylic acid composition is produced. In another embodiment, the invention relates to compositions of crude acrylic acid having the bio-based content of the glacial acrylic acid greater than about 3%, used to make acrylic esters, in particular, produced by the steps comprising: a. providing an aqueous solution of acrylic acid comprising: 1) acrylic acid; and 2) lactic acid, lactic acid derivatives, or mixtures, wherein said aqueous solution of acrylic acid is essentially free of maleic anhydride, furfural, and formic acid; b. extracting said aqueous solution of acrylic acid, with a solvent to produce an extract; c. drying said extract to produce a dried extract; d. distilling said dried extract to produce distilled acrylic acid composition; and e. determining the acrylic acid purity of said purified acrylic acid liquid composition, and if the purity is less than about 94 wt% acrylic acid, repeating said cooling, partially melting, decanting, and fully melting steps on the purified acrylic acid liquid composition until a purity of about 94 wt% acrylic acid is achieved and said crude acrylic acid composition is produced.EFFECT: production of acrylic acid.41 cl, 5 ex |