Design of practical Ce/CoMnAl-LDO catalyst for low-temperature NH3-SCR
Xinyu Zhang, Qinghua Yan, Qiang Wang
Abstract
A highly active Ce/CoMnAl-LDO catalyst for low-temperature NH3-SCR with good thermal stability and SO2/H2O resistance was designed from layered double hydroxides (LDHs). At 100–250 °C, Ce0.5/Co1Mn0.5Al0.5Ox-LDO showed practically ~100% NOx conversion compared to Ce-Co-Mn/γ-Al2O3 (63.4–90.3%) of the same metal composition prepared by the common wet-impregnation method. The LDO catalytic material showed very stable NOx conversion of 83.3% at 200 °C after 10 h test with 100 ppm SO2 in the feed stream, superior performance when compared to the control catalysts Co1Mn0.5Al0.5Ox (60.2%) and Ce-Co-Mn/γ-Al2O3 (28%). The thermal stability and resistance to water vapor were also investigated. Various studies suggested that the excellent performance of Ce0.5/Co1Mn0.5Al0.5Ox-LDO can be attributed to the high dispersion of active metal species, large specific surface area, moderate redox capacity and strong acidity.