Calcium-Poison-Resistant\nCu/YCeO<sub>2</sub>–TiO<sub>2</sub> Catalyst for the Selective\nCatalytic Reduction of NO with\nCO and Naphthalene in the Presence of Oxygen

The pollution from industrial processes based on biomass\ncombustion\nis still an ongoing problem. In the present contribution, the selective\ncatalytic reduction of NO with CO and naphthalene is carried out in\nthe presence of 10% oxygen. The accumulation of alkaline and alkaline\nearth metals during biomass combustion is here simulated by the addition\nof calcium to a Cu-impregnated YCeO<sub>2</sub>–TiO<sub>2</sub> support. The results show that a high dispersion of copper is obtained,\nwhich is resistant to the accumulation of calcium. Full conversion\nof CO and naphthalene is achieved above 200 °C, whereas NO conversions\nof 80, 90, and 87% are obtained for the catalysts with Ca loadings\nof 2.6, 5.2, and 13%, respectively, at 350 °C. It is proposed\nthat the high activity of the catalysts is ascribed to the formation\nof Cu–O<sub>x</sub>–Ce species and that the accumulation\nof Ca acts as a barrier to avoid copper sintering. It was found that\ndifferent forms of carbonate and nitrite/nitrate species form during\nreaction, coexisting as adsorbed species during the SCR reaction.\nThe selectivity to N<sub>2</sub> was almost 100% in all cases, due\nto the small presence of NO<sub>2</sub> in the reactor outlet (no\nN<sub>2</sub>O was detected in any conditions).