A superior Fe-Zr mixed oxide catalyst for the simultaneous reduction of NO and SO2 with CO

A series of Fe-Zr mixed-metal oxides were prepared and examined for the simultaneous reduction of NO and SO 2 with CO. The catalyst containing 40 mol% exhibited near-complete conversion of both pollutants at a minimum temperature of 350 °C and a GHSV of 90,000 h −1 . The addition of Fe 3+ to ZrO 2 decreased the crystallinity of the latter phase and significantly enhanced surface area. Concentrations of 30 mol% or greater produced segregated FeO x phases, which affected catalytic performance in distinctly different ways: supported Fe 3+ (30 mol%) possessed similar activity to doped Fe 3+ ; α-Fe 2 O 3 (50 mol%) inhibited activity due to its’ lower reducibility; an amorphous phase (40 mol%) promoted iron-weighted areal activity. A complete identification of the ambiguous component was not successfully established, but the obtained properties revealed that it exhibited weaker interaction with the support and had a size greater than that of oligomeric-Fe 2 O 3 yet smaller than 3 nm.