HYDROGENATION OF CYCLOPENTADIENE TO FORM CYCLOPENTENE

IMPROVEMENT IN HYDROGENATION OF CYCLOPENTADIENE TO FORM CYCLOPENTENE There is disclosed an improved process for selectively hydrogenating cyclopentadiene to form cyclopentene in the presence of a catalyst comprising (A) a hydrocarbon-soluble nickel compound such as nickel salts of carboxylic acids or organo nickel compounds, (B) an organo reducing agent such as organoaluminum compounds or lithium alkyl compounds and (C) pyridine, the improvement being that the soluble nickel compound and the pyridine are employed in amounts wherein the mole ratio of aluminum or lithium to the nickel ranges from 7/1 to 11/1 and the mole ratio of the pyridine to the nickel compound ranges from 1/1 to 2.5/1.