SO2 resistant soot oxidation catalysts based on orthovanadates

Abstract Metal orthovanadates based on Fe, Al and Ce were prepared by co-precipitation and their structural, morphological and reduction properties were characterized by means of XRD, BET and temperature programmed reduction (H 2 -TPR). Catalytic soot oxidation was carried out with thermogravimetric analysis (TGA) and temperature programmed oxidation (TPO), respectively, to study the influence of the soot-catalyst contact (tight or loose) as well as the influence of SO 2 contamination on the catalyst's activity. The catalysts were compared with CeO 2 as reference material. Under tight contact mode, metal orthovanadates were able to oxidize soot at 466–483 °C while in loose contact mode their activity was close to that of CeO 2 . However, the former did not suffer an activity loss due to SO 2 poisoning, which is attributed to less adsorptive interactions between SO 2 and the vanadates as could be proven by FT-IR and Raman spectroscopy.