High Resistance of Cu–Ferrierite to Coke Formation During NH3-SCR in the Presence of n-Decane

Selective catalytic reduction of NO x by NH 3 over Cu–FER and Cu–ZSM-5 in the presence of n -decane and SO 2 was investigated. NO x conversion over Cu–ZSM-5 decreased in the presence of n -decane, owing to inhibition of the active sites by coke formation. In contrast, coke formation was negligible over Cu–FER, which maintained its NO x conversion activity even in the presence of decane. Coke formation was negligible over H–ZSM-5 and H–FER supports, which suggests that Cu species were involved in coke formation. Temperature-programmed reduction by H 2 and electron spin resonance spectroscopy indicated that [Cu–O–Cu] 2+ was probably the Cu species involved in coke formation over Cu–ZSM-5.