The effect of copper on benzene hydrogenation to cyclohexane over Ni/Al2O3 catalyst

•Copper as an efficient modifier of Ni/Al2O3 catalyst for benzene to cyclohexane hydrogenation.•Considerably better selectivity of Ni–Cu catalyst compared to the reference one due to enrichment of the catalyst surface with copper.•Improvement of the catalytic activity upon addition of up to 20wt% CuO and decrease of the activity above that content.