CATALYST FOR CYCLIZATION OF PENTADIENE-1,3 INTO CYCLOPENTENE AND CYCLOPENTANE, PROCESS FOR MAKING SAME AND METHOD FOR USING IT

A catalyst for cyclization of pentadiene-1,3 into cyclopentene and cyclopentane comprises a membrane made from an alloy of 84.58-94.95 by mass of palladium, 4.975-14.99% by mass of ruthenium or rhodium and 0.05-0.5% by mass of zinc or gallium and consisting of a non-porous layer and a porous layer positioned on one or both sides of the non-porous layer. The catalyst may be prepared by a process comprising application, on one or both sides of a membrane made from an alloy consisting of 85-95% by mass of palladium and 5-15% by mass of ruthenium or rhodium, of zinc or gallium at a thickness ratio of the layer of zinc or gallium to the membrane of 1:4-20 respectively; keeping the membrane with zinc applied there onto at a temperature of 230-250% and with gallium-at a temperature of 30-120 DEG C to ensure diffusion of zinc or gallium into the membrane; chemical recovery of zinc or gallium from the membrane, the recovery of zinc or gallium being conducted to a content thereof in the catalyst of 0.05 to 0.5% by mass.