Catalytic deep oxidation of volatile organic compounds over fluorinated carbon supported platinum catalysts at low temperatures

A novel low-temperature oxidation catalyst, Pt/fluorinated carbon/ceramic (Pt/FCC), has been compared with a conventional Pt/alumina catalyst using the oxidation of benzene as a model reaction to examine the effectiveness of the catalyst for the deep oxidation of volatile organic compounds (VOCs) at temperatures below 200 degrees C. For an equivalent platinum loading, the activity of the Pt/FCC is comparable to that of the Pt/alumina catalyst in dry feed conditions. However, when water vapor is present in the feed stream, the Pt/FCC catalyst shows significantly higher activity than the Pt/alumina catalyst. Under humid conditions, the benzene oxidation on the Pt/alumina catalyst is substantially inhibited by the adsorption of water vapor on both the alumina support and on the Pt sites, with the effect of alumina being more significant than that of Pt sites. For the Pt/FCC catalyst, the support hydrophobicity prevents the adsorption of water on the support, and the adsorption of water vapor on the Pt sites which results in only a slight decrease in activity, suggesting that the Pt/FCC catalyst is more suitable for the deep oxidation of VOCs when the feed gas contains a significant amount of humidity.