1. 1. Hydrogen transfer to the zone of hydrogenation of cyclopentadiene through a membrane catalyst from a Pd alloy with 10 vol. % Ru increases the rate and selectivity of hydrogenation to cyclopentene, compared with the experiment carried out at the same temperature and partial reagent pressure, but without hydrogen transfer to the membrane catalyst. 2. 2. Joining dehydrogenation of isopropyl alcohol and hydrogenation of cyclopentadiene increases even more the rate of both reactions, the selectivity of conversion of cyclopentadiene to cyclopentene and increases the amount of hydrogen formed during dehydrogenation of alcohol that is passed through the membrane. © 1979.