LIQUID-PHASE SELECTIVE HYDROGENATION OF 1-HEPTYNE OVER Au-Pd/TiO2 CATALYSTS

For the former sample, the state of dispersion of Pd on TiO2 changed during the loading of Au, resulting in the formation of small Au-Pd alloy particles and thus changing the electronic properties of Pd species. The electronic properties of Pd on Pd/Au/TiO2_100 were not so different from those of monometallic Pd/TiO2_100.

Moreover the nanocrystalline TiO2 materials (9 and 15 nm) were synthesized by the solvothermal method and employed as the supports for preparation of bimetallic Au/Pd/TiO2 catalysts. The Pd metal and/or Pd-Au alloy formed on the TiO2_9 (< 1 nm) were smaller than on TiO2_15 (2-3 nm) and on TiO2_100 (4-10 nm). All the catalysts were selective to 1-heptene (> 95%) until close to the complete conversion of 1-hetyne.