Design of bifunctional catalysts for nitrogen(I), (II) oxides reduction by C1-, C3–C4-hydrocarbons at H2O and SO2 presence

Results of design of metal oxide (Co, Cr, Ce, In, Fe) catalysts including those doped with Rh (Pd) supported on ZrO2, Al2O3, H-ZSM-5 and their binary compositions for reduction of NO, N2O by C1, C3–C4-hydrocarbons and CO in gas flows containing oxygen, H2O and SO2, are presented. SCR-activity of Co–In-oxide catalysts towards NO depends on the nature of support and the sequence of active components’ application, and the catalysts (In2O3–CoO)/ZrO2 exhibit high resistance against moisture and sulfur dioxide. In combined reduction of nitrogen(I), (II) oxides with C3–C4 alkanes (SCR-conditions) at 400–450 °C, higher conversions for NO (60–78%) were observed on the Co-containing catalysts, whereas for N2O (90–95%) – on the Fe-containing ones supported on the H-ZSM-5. Composites over structured support Pd/Co3O4–CeO2/cordierite showed high activity in NO + N2O + CO reactions (95–99% conversion of N2O and NO at 200–300 °C) in the presence of H2O.