X‐ray photoelectron spectroscopic (XPS) study of DeNO_x catalysts after exposure to slag tap furnace flue gas

Abstract

X-ray photoelectron spectroscopy has been used to investigate the composition of both the surface of DeNO, catalysts (Ti: Mo: V = 92 : 6 : 2 and Ti : W : V = 85 : 10: 5 at.%) and the material deposited from the flue gas. In spite of the charging of the surface in the spectrometer, it was possible to perform both qualitative and quantitative analysis. The deposits primarily contain Ca, Si, 0, S, As, P and N. Oxidation numbers of Ca, Si, Ti, Mo, W, S and N were determined from chemical shifts in combination with line widths. There are, however, problems with the determination of the oxidation state of As owing to an influence of the exciting Al Ka radiation on the oxidation state. Nevertheless, As seems to exist both as As3+ and As5+.

Environmental Catalysis — Stationary Sources

“…Rademacher et al [125] used X-Ray photoelectron spectroscopy for the characterization of two types of catalysts which were exposed to flue gas of a slag tap furnace with 100% ash recirculation for 1800 h. These catalysts were Moo3 / V z 0 5 on SiO2 and W03/V205 on SiO;!/P205/A1;!03. Elements such as Ca, Si, S, As, P, and N were found.…”