CATALYTIC OXIDATION OF ELEMENT MERCURY IN SIMULATED FLUE GAS BY HEMATITE AND MAGHEMITE NANOPARTICLES
Rod-shaped hematite and maghemite nanoparticles with the diameter of 40～80 nm and the length of 200～400nm were synthesized by pressure-precipitation method. The crystal phase structure，surface area ,particle size and morphology of the synthesized samples were characterized by XRD,BET and SEM respectively. The experiments of element mercury catalytic oxidation using Fe-based nanoparticles has been done in a fixed bed reactor，and the effects of oxygen concentration , bed floor temperature and water vapour on the Hg oxidation has been discussed. The results show that both nano hematite and maghemite can catalyze and oxidize element mercury, while α-Fe2O3 and γ-Fe2O3 with ordinary-size almost have no mercury oxidation capability, furthermore, the Hg0 oxidation efficiency can reach about 40 ％ when using nano maghemite as catalyst and is much higher than that of nano hematite（about 12 ％）. No obvious mercury oxidation was detected in the pure N2 atmosphere, which indicates that oxygen is required in the gas stream for mercury oxidation. Bed floor temperature has important effect on Hg oxidation, the increase of bed floor temperature and oxygen concentration can promote mercury oxidation and lead to higher Hg oxidation efficiency, The presence of water vapour shows different effect on mercury oxidation depending on its concentration The lower content of water vapour can promote mercury oxidation slightly, which results from the hydroxyl produced on the surface of nano samples. while the higher content of water vapour inhibits mercury oxidation.
mercury ozidation hematite maghemite nanoparticles
Fanhai KONG Jianrong QIU Zhihui AI Hao LIU Wenting XING Xiao SONG
State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430079 Key Laboratory of Pesticide and Chemical Biology, Ministry of Education, College of Chemistry, Centr
国际会议
第六届煤燃烧国际会议(The 6th International Symposium on Coal Combustion)
武汉
英文
843-847
2007-12-01（万方平台首次上网日期，不代表论文的发表时间）