METHOD OF PRODUCING ISOPRENE Russian patent published in 2011 - IPC C07C11/18 C07C1/20 C07C2/86 

FIELD: chemistry.

SUBSTANCE: invention relates to a method or producing isoprene via liquid-phase reaction of components of the raw materials - formaldehyde and, possibly, substances which are a source of formaldehyde, with tert-butanol, possibly isobutylene or substances which are a source of isobutylene, and possibly intermediate products of isoprene precursors, in the presence of a strong acid catalyst and water using molar excess of tert-butanol or isobutylene to formaldehyde or substances which are a source of formaldehyde, at temperature and pressure which facilitate transition of isoprene into the vapour phase followed by extraction thereof, which is carried out while feeding heat into the reaction zone of the reactor which is fitted with a mass-exchange cap, owing to circulation of the heated acid aqueous layer while ensuring temperature fall on the height of the reaction zone, characterised by that, the reactor has one or more extra series-arranged reaction zones fitted with a mass-exchange cap, raw material is fed into each zone through distribution devices, wherein heat is further fed into the additional zones by the vapour phase through the distribution devices from the previous reaction zone while maintaining temperature and pressure which facilitate transition of the main component of tert-butanol and isobutylene into vapour phase and temperature fall of 3-7°C on the height of each reaction zone.

EFFECT: reduced formation of by-products by more than 2,5 times with respect to output of isoprene while simultaneously reducing energy output of the process.

1 cl, 2 tbl, 2 ex, 2 dwg