METHOD OF PRODUCING ETHYLIDENE NORBORNENE Russian patent published in 2013 - IPC C07C5/25 C07C4/22 C07C13/43 C07C2/50 C07C7/04 

FIELD: chemistry.

SUBSTANCE: invention relates to a method of producing ethylidene norbornene (ENB). The method comprises the following steps: a) feeding dicyclopentadiene into a first reactor for the thermal cracking of dicyclopentadiene to cyclopentadiene, carried out in inert heat transfer fluid having a boiling point >230° C, said thermal cracking being carried out at a temperature lower than the boiling point of said heat transfer fluid and lies between 200°C and 300° C; b) feeding said cyclopentadiene produced at step a) into a second reactor in which said cyclopentadiene reacts with 1,3-butadiene to form vinyl norbornene (VNB); c) feeding said VNB produced at step b) into a third reactor in which a catalytic isomerisation of VNB to ethylidene norbornene (ENB) is carried out; d) collecting said ENB. Said step a) is characterised by that: i) said dicyclopentadiene fed to said step a) contains primary dicyclopentadiene from cracking containing up to 10 wt % of tetrahydroindene (THI), and recycled dicyclopentadiene containing tetrahydroindene (THI) recycled from said step b) of formation of vinyl norbornene; ii) said dicyclopentadiene containing said THI is fed into said heat transfer fluid and is in contact with it for a time of less than 1 minute; iii) the formed cyclopentadiene vaporises into the gas phase established above said liquid phase and is continuously removed from said first reactor; iv) a part of said heat transfer fluid substantially free of dicyclopentadiene and rich in THI is continuously fed into a fractionation column, said THI being collected at the top of said column and said heat transfer fluid being collected at the bottom of said column; v) said heat transfer fluid purified in step iv) is recycled to said first reactor of said step a).

EFFECT: high efficiency of the method.

15 cl, 2 ex, 1 dwg