AIChE Journal, Vol.56, No.6, 1545-1556, 2010
Novel Microfibrous-Structured Silver Catalyst for High Efficiency Gas-Phase Oxidation of Alcohols
Novel microfibrous-structured silver catalysts were developed for gas-phase selective oxidation of mono-/aromatic-/di-alcohols. Sinter-locked three-dimensional microfibrous networks consisting of 5 vol % 8-mu m-Ni (or 12-mu m-SS-316L) fibers and 95 vol % void volume were built up by the papermaking/sintering processes. Silver was then deposited onto the surface of the sinter-locked fibers by incipient wetness impregnation method. At relatively low temperatures (e.g., 380 degrees C), the microfibrous-structured silver catalysts provided quite higher activity/selectivity compared to the electrolytic silver. The microfibrous Ag/Ni-fiber offered much better low-temperature activity than the Ag/SS-fiber. The interaction at Ag particles and Ni-fiber interface not only visibly increased the active/selective sites of Ag+ ions and Ag-n(delta+) clusters hut also significantly promoted their low-temperature reducibility and ability for O-2 activation. In addition, the microfibrous structure provided a unique combination of large void volume, entirely open structure, high thermal conductivity and high permeability. (C) 2009 American Institute of Chemical Engineers AIChE J, 56: 1545-1556, 2010
Keywords:silver catalysis;monolithic catalyst;microstructured reactor;fibers;alcohol;gas-phase oxidation