Disclosed herein is a process for dehydrogenating a hydrocarbon with a dehydrogenation catalyst comprising a step of activating the catalyst precursor in a H2-containing atmosphere. A particularly advantageous activation process includes heating the catalyst precursor to a temperature in a range from 400° C. to 600° C. The process of the present disclosure is particularly advantageous for dehydrogenating cyclohexane to make benzene.