| Abstract: Reducibility and characteristics of CuO/Sn0.8Ti0.2O2 catalysts were examined by using a microreactor-GC NO+CO reaction system, BET, TG-DTA, FTIR, XRD and H2-TPR techniques.
CuO/Sn0.8Ti0.2O2 had high activity in NO+CO reaction, showing 93% NO conversion at 300 ℃ in air, and 100% NO conversion at 225 ℃ after
H2 pretreatment. The pore size distribution of Sn0.8Ti0.2O2
was mainly as micro-pores and meso-pores (1~5 nm), and the specific surface area and total pore volume of
Sn0.8Ti0.2O2 were 69 m2·g-1 and 0.15
cm3·g-1, respectively. As shown by XRD analysis, there was no CuO crystal diffraction peak at 9%CuO loading, but two CuO crystal diffraction peaks at 2θ 35.5° and 38.7° were present at 12% CuO loading. FTIR detected the adsorption of NO and CO on the surface of reduced
12%CuO/Sn0.8Ti0.2O2. The Cu2+ sites and support surface adsorbed NO, and the process of NO adsorption led to the formation of
N2O and NO3-. In contrast, the Cu+、Cu0 sites and support surface adsorbed CO, and when the mixed gases of NO and CO were adsorbed by support surface, no
NO3- was formed. H2-TPR showed four reduction peaks (α, β, γ and δ). The α, β and γ peaks were the reductions of CuO species, and the δ peak was the reduction of
Sn0.8Ti0.2O2. |
