Process for producing cycloolefins

Abstract From the Canadian patent

A process for producing a cycloolefin in high selectivity and yield by partial hydrogenation of a monocyclic aromatic hydrocarbon with hydrogen is disclosed. In this process the hydrogenation reaction is carried out under a neutral or acidic condition in the presence of: i) a particulate hydrogenating catalyst mainly comprising metallic ruthenium having an average crystallite size of 200 .ANG. or less, ii) at least one zinc compound as a promoter iii) at least one additive selected from the group consisting of oxides, hydroxides and hydrates thereof Zr, Hf, Ti, Nb, Ta, Cr, Fe, Co A?, Ga, and Si, and, iv) water.