Size-controlled Pd Nanoparticles Supported on α-Al2O3 as Heterogeneous Catalyst for Selective Hydrogenation of Acetylene

Size-controlled Pd nanoparticles (PdNPs) were synthesized in aqueous solution, using sodium carboxymethyl cellulose as the stabilizer. Size-controlled PdNPs were supported on alpha-Al2O3 by the incipient wetness impregnation method. The PdNPs on alpha-Al2O3 support were in a narrow particle size distribution in the range of 1-6 nm. A series of PdNPs/alpha-Al2O3 catalysts were used for the selective hydrogenation of acetylene in ethylene-rich stream. The results show that PdNPs/alpha-Al2O3 catalyst with 0.03% (by mass) Pd loading is a very effective and stable catalyst. With promoter Ag added, ethylene selectivity is increased from 41.0% to 63.8% at 100 degrees C. Comparing with conventional Pd-Ag/alpha-Al2O3 catalyst, PdNPs-Ag/alpha-Al2O3 catalyst has better catalytic performance in acetylene hydrogenation and shows good prospects for industrial application.