METHOD OF PROPYLENE PRODUCTION BY RECYCLING OF HEAVY FRACTIONS Russian patent published in 2017 - IPC C07C6/04 C07C11/06 

FIELD: manufacturing technology.

SUBSTANCE: invention relates to two versions of method of propylene production. One of versions includes: metathesis reaction of raw supply stream consisting of mixture of n-butene with ethylene in presence of metathesis catalyst to form fraction containing propylene, ethylene, butene and C₅₊ olefins, 2-pentene and 3-hexene; extraction of propylene from ethylene, butene and C₅₊ olefins from fraction of metathesis products; and recirculation of at least part of C₅₊ olefins for metathesis reaction recycled C₅₊ olefins are converted into propylene and butene, wherein ethylene is introduced into metathesis reaction at ratio, which is sufficient for maintaining reaction, where C₄₊ ratio for reaction with metathesis catalyst ranges from 0.3:1 to 3:1 and at least 5 % of C₅₊ olefins return into metathesis reaction.

EFFECT: use of recycling of C₅₊ olefin gasoline increases efficiency of method with low total flow through metathesis reactor.

11 cl, 3 dwg