Preparation process of 5-ethylidene-2-norbornene

A preparation process of 5-ethylidene-2-norbornene, comprising:

• step a-1 of introducing dicyclopentadiene (DCPD) into a DCPD decomposition reactor (110) to thermally decompose the DCPD, wherein the DCPD decomposition reactor includes a thermal decomposition reaction portion adjusted to a temperature of 300 to 500° C.;
• step a-2 of introducing a product of the step a-1 into a cyclopentadiene (CPD) purification tower (120);
• step b-1 of introducing 1,3-butadiene (BD), a solvent, and cyclopentadiene separated from a top of the CPD purification tower (120) into a Diels-Alder reactor (210) to react the same, wherein the solvent has a boiling point of 70 to 140° C.;
• step b-2 of introducing a product of the step b-1 into a BD removal tower (220) to recover 1,3-butadiene from the top thereof;
• step b-3 of introducing a mixture at a bottom of the BD removal tower (220) into a desolvation tower (230) to recycle the solvent and unreacted raw materials recovered from a top of the desolvation tower (230) to the DCPD decomposition reactor (110);
• step c of introducing a mixture at a bottom of the desolvation tower (230) into a 5-vinyl-2-norbornene (VNB) separation tower (300) to separate 5-vinyl-2-norbornene;
• and
• step d of introducing the 5-vinyl-2-norbornene into an isomerization reactor (410) to react the same.