METHOD OF ISOPRENE PRODUCTION Russian patent published in 2008 - IPC C07C11/18 C07C2/86 

FIELD: chemistry.

SUBSTANCE: invention relates to the method of isoprene production by means of liquid-phase interreaction of formaldehyde and isobutylene or a substance from which they are derived, for example 4,4-dimethyl-1,3-dioxane and trimethyl carbinol, with aqueous solution of acid catalyst. The method is carried out at high temperature and pressure with deriving resultants and balance quantity of water in the form of vaporous steam, with further cooling, condensation and separation on water and organic layers with processing of organic layer that includes extraction of recycle isobutylene, final isoprene, recycle trimethyl carbinol and high boiling residual matter, and with processing of water layers that involves extraction of organic products including trimethyl carbinol with the derivation of liquid draught of catalyst aqueous solution for extraction, with further return in the synthesis zone at the same time the extraction of trimethyl carbinol from the final products is carried out through water extraction with the following final aqueous solutions derivations. The method allows increasing of isoprene yield up to 71.6% according to formaldehyde and 73.9% according to isobutylene.

EFFECT: increase of isoprene yield.

5 cl, 6 dwg, 7 ex