METHOD OF PRODUCING ISOPRENE Russian patent published in 2012 - IPC C07C11/18 C07C2/86 C07C1/20 C07C7/10 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing isoprene via liquid-phase reaction of formaldehyde and isobutylene and/or substances which are sources thereof, for example, 4,4-dimethyl-1,3-dioxane and trimethyl carbinol, in the presence of an aqueous solution of an acid catalyst at high temperature and pressure while extracting a vapour-liquid stream of reaction products and water from the reaction zone. Further, the vapour-liquid stream is separated, cooled, condensed and split into aqueous and oily layers, followed by extraction of isoprene from the oily layer. The method is characterised by that before extracting isoprene, the oily layer is washed with water in a countercurrent column at temperature 20-60°C, pressure 0.4-1.0 MPa in weight ratio (10-50):1, respectively.

EFFECT: method reduces loss of isoprene during extraction thereof.

3 cl, 1 tbl, 4 ex, 1 dwg