High catalytic activity for formaldehyde oxidation of AgCo/APTES@MCM-41 prepared by two steps method

摘要

We reported here a novel synthesis procedure to prepare a highly active bimetallic AgCo/APTES@MCM-41 catalyst. Complete oxidation of formaldehyde was achieved at temperature as low as 90 °C over the bimetallic catalysts with Ag/Co=3/l (mass ratio). N2 isotherms, small-angle XRD results suggested that both Ag and Co species were well dispersed on the support, and the pore structure of the support was not destroyed after introducing the active metal. The formation of the strong metal-metal interaction (SMMI) between Ag and Co in the bimetallic catalysts due to the electron transfer between each other resulted in the high Co~(3+)/Co~(2+) ratio and good low-temperature reducibility. And more surface active oxygen species (O_(surf)) formed on the surface of the bimetallic catalysts. All these factors gave rise to the high formaldehyde catalytic oxidation activity in AgCo bimetallic catalysts. The possible structure changes of bimetallic catalysts and the reaction path for the complete oxidation of formaldehyde over AgCo bimetallic catalyst was also proposed.