Remarkable N < sub > 2 < /sub > selectivity enhancement of NH < sub > 3 < /sub > -SCO reactions over V < sub > 0.5 < /sub > /Pt < sub > 0.04 < /sub > /TiO < sub > 2 < /sub > catalyst through Cu-Er co-modification

Environ Sci Pollut Res Int. 2023 Sep 18. doi: 10.1007/s11356-023-29781-2. Online ahead of print.ABSTRACTPt-V bimetallic catalysts maybe promising substitutes to precious metal catalysts for selective catalytic oxidation (SCO) of NH3. But it remains a major challenge for Pt-V bimetallic catalysts to pursue high NH3 conversion rate and N2 selectivity simultaneously. In this work, both Cu and Er were adopted to modify V0.5/Pt0.04/TiO2 catalyst (denoted as V/PT), and the influences of Cu and Er doping amounts on NH3-SCO performance of V/PT catalysts were investigated systematically. The results indicated that the co-modification of Cu and Er imposed little influence on NH3 conversion efficiency, but significantly boosted N2 selectivity. Compared with other Cu-Er-modified V/PT catalysts, CEV/PT-4 catalyst exhibited outstanding NH3-SCO performance, which attained completely 100% NH3 conversion efficiency and > 90% N2 selectivity in the temperature range of 225-450 °C. It was significantly superior to the NH3-SCO performance of most previously reported catalysts. The characterization results indicated that the adequate doping amounts of Cu and Er resulted in an obvious enhancement on redox property and surface acidity of CEV/PT-4 catalyst. It also led to abundant Pt0 and surface chemisorbed oxygen species on catalyst surface, which facilitated the oxidation of NH3 to NOx and enhanced i-SCR reactions. In situ DRIFTS results showed that -NH2 species on the surface of CEV/PT-4 cata...
Source: Environmental Science and Pollution Research International - Category: Environmental Health Authors: Source Type: research