ISOPRENE PRODUCING METHOD

摘要

The invention relates to the petrochemical industry. Isoprene is produced by a liquid-phase interaction of formaldehyde with isobutylene comprising isobuthylene-containing fractions of isobutane dehydrogenation and oil fractions of catalytical cracking or pyrolyse. The process is carried out in two stages in a running water medium containing phosphoric acid in the form of a catalyst. The first stage consists in producing a mixture of methylbutainediol and dimethyldioxane which are converted, at the second stage, into isoprene extractable from the reaction medium by means of flowing organic solvent. The use of a countercurrent scheme for bringing into contact organic products partially soluble in water phase makes it possible to use the isobuthylene-containing fractions. For carrying out said method, the structural design for an isothermic countercurrent liquid-phase case-tubular column reactor is disclosed. A regular spiral nozzle is used in the form of a contacting device in reactors and in other process heat-mass-exchange equipment. The use of isobuthylene-containing raw material in said process extends a raw material resource base and improves the efficiency of the method. Said method makes it possible to simultaneously produce highly-pure isoprene and isobuthylene products.