Effects of NO2 and SO2 on selective catalytic reduction of nitrogen oxides by ammonia.
The selective catalytic reduction (SCR) characteristics of NO and NO(2) over V(2)O(5)-WO(3)-MnO(2)/TiO(2) catalyst using ammonia as a reducing agent have been determined in a fixed-bed reactor at 200-400 degrees C. The presence of NO(2) enhances the SCR activity at lower temperatures and the optimum ratio of NO(2)/NO(x) is found to be 0.5. During the SCR reactions, there are some side reactions occurred such as ammonia oxidation and N(2)O formation. At higher temperatures, the selective catalytic oxidation of ammonia and the nitrous oxide formation compete with the SCR reactions. The denitrification (DeNO(x)) conversion decreases at lower temperatures but it increases at higher temperatures with increasing SO(2) concentration. The presence of SO(2) in the feeds inhibits N(2)O formation.
Goo
Jeong Hoi
JH
Department of Chemical and Biomolecular Engineering, Energy and Environment Research Center, Korea Advanced Institute of Science and Technology, 305-701 Daejeon, Republic of Korea.
Irfan
Muhammad Faisal
MF
Kim
Sang Done
SD
Hong
Sung Chang
SC
D000641:Ammonia / Q000737:chemistry*; D002384:Catalysis; D009585:Nitrogen Dioxide / Q000737:chemistry*; D009589:Nitrogen Oxides / Q000737:chemistry*; D010084:Oxidation-Reduction; D013458:Sulfur Dioxide / Q000737:chemistry*
D009589:Nitrogen Oxides; D013458:Sulfur Dioxide; D000641:Ammonia; D009585:Nitrogen Dioxide