Membrane catalysts for partial hydrogenation of 1,3-butadiene: catalytic properties of palladium nanoclusters synthesizes within diblock copolymer films

Palladium nanoclusters were synthesized within microphase-separated diblock copolymer films of [MTD](113)[Pd(Cp-N)PA](50) (MTD = methyltetracyclododec ene, Cp-N = endo-2-(cyclopentadienylmethyl)norborn-5-ene PA= eta(3)-1-pheny lallyl). The organometallic repeat units were reduced by exposing the films to hydrogen at 100 degrees C, leading to the formation of nearly monodispe rse palladium nanoclusters. TEM was used to measure the cluster size. The n anocomposite films were active and selective catalysts for the gas phase hy drogenation of 1,3-butadiene. Selectivity for butenes was improved by lower ing the hydrogen partial pressure, and lower temperature favored formation of 1-butene over 2-butenes. (C) 1999 Elsevier Science S.A. All rights reser ved.