The present invention relates to a process for separating the isoprene, 1,3-pentadiene
and dicyclopentadiene from a C5 cuts, comprising dimerization of the cyclopentadiene
and selective catalytic hydrogenation. The second extractive rectification step
can be omitted, because the alkynes are removed through selective catalytic hydrogenation
prior to the extractive rectification. As a result, the solvent-recovering units
can be simplified, and thus the process as a whole can be optimized. Correspondingly,
the investment and energy consumption, the operation cost, and finally the production
cost can be substantially reduced.