Promotion of Ni/H-BEA by Fe for NO_x reduction with propane in a lean-burn condition

The effect of iron addition to Ni/H-BEA on selective catalytic reduction of NO_x with propane (C₃H₈-SCR) was investigated under a lean-burn condition. The addition of iron significantly lowered the optimum reaction temperature of Ni/H-BEA from 623 to 573 K. The 3Ni-1Fe/H-BEA catalyst had the highest activity among samples with different bimetal loading. NO_x conversion of 100% was obtained at 573 K. Oxygen played an important role in activating NO and propane during the C₃H ₈-SCR reaction. NO_x conversion increased as the C ₃H₈/NO molar ratio increased. A complete conversion of NO_x was achieved with C₃H₈/NO = 1.25 at 573 K. The catalytic activity was inhibited slightly at a low SO₂ concentration (100 ppm) but decreased dramatically at a high SO₂ concentration (600 ppm) over different catalysts. The introduction of 10% water also exhibited a negative impact on the reduction of NO_x. The catalytic activity of Ni-Fe/H-BEA represented only a slight drop in the presence of 100 ppm SO₂ and 10% H₂O. The addition of iron to Ni/H-BEA notably improved the tolerance of SO₂ and H₂O.