Di-metal-doped sulfur resisting perovskite catalysts for highly efficient H2-SCR of NO.

Lanthanide perovskite catalysts doped with limited palladium (to improve activity) and cerium (to improve sulfur resistance) were prepared using sol-gel method. In different B sites, lanthanide perovskites were studied at harsh conditions for H2 selective catalytic reduction of NO. The activity sequence was as follows: LaCeMnPd > LaCeCoPd > LaCeFePd. LaCeMnPd had a high NO conversion of 96.6% at only 150 °C. And it also had a surprising SO2 resistance in different SO2 concentrations. After cutting out SO2, NO conversion recovered rapidly to its original level, indicating that the slight deactivation was reversible. In addition, the effect of gas hourly space velocity, H2/NO ratio, O2, and SO2 concentration was studied. And XRD, energy-dispersive X-ray, SEM, XPS, H2-temperature programmed reduction, and NH3-temperature programmed desorption were performed to characterize the catalysts. Graphical abstract ᅟ.