Selective Catalytic Reduction of NOx with NH3 on a Cr-Mn Mixed Oxide at Low Temperature

✍ Scribed by Zhihang CHEN; Xuehui LI; Xiang GAO; Yanbin JIANG; Yangxiao LÜ; Furong WANG; Lefu WANG

• Publisher: Elsevier Science
• Year: 2009
• Weight: 501 KB
• Volume: 30
• Category: Article
• ISSN: 1872-2067
• DOI: 10.1016/s1872-2067(08)60083-2

✦ Synopsis

A series of Cr-Mn mixed oxide catalysts were prepared by the citric acid method and characterized by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy. The effect of Cr/(Cr + Mn) molar ratio on activity for the selective catalytic reduction (SCR) of NO x by ammonia in the presence of excess oxygen at low temperature (80-220 °C) was studied. A 98.5% NO x conversion with 100% selectivity for N 2 was obtained with Cr(0.4)-MnO x mixed oxide (Cr/(Cr + Mn) molar ratio = 0.4) at 120 °C and a space velocity of 30000 h 1 . XRD results showed that the addition of chromium to MnO x produced a CrMn 1.5 O 4 crystal phase, which played an important role in low-temperature SCR.