Investigation of fluorescence characterization and electrochemical behavior on the catalysts of nanosized Pt-Rh/y-AI203 to oxidize gaseous ammonia

作     者：Chang-Mao HUNG Wen-Liang LAI Jane-Li LIN 

作者机构：Department of Vehicle Engineering Yung-Ta Institute of Technology and Commerce Pingtung 909 China Department of Environmental Science and Occupational Safety and Hygiene Tajen University Pingtung 907 China 

出 版 物：《Frontiers of Environmental Science & Engineering》 (环境科学与工程前沿（英文）)

年 卷 期：2013年第7卷第3期

页      面：428-434页

核心收录：

学科分类：081704[工学-应用化学] 081705[工学-工业催化] 07[理学] 08[工学] 0817[工学-化学工程与技术] 080502[工学-材料学] 0805[工学-材料科学与工程（可授工学、理学学位）] 0703[理学-化学] 070301[理学-无机化学] 

基　　金：the National Science Council of China  for financially supporting this research under Contract 

主　　题：ammonia (NH3) nanosized Pt- Rh/γ-A12O3catalyst excitation-emission fluorescent matrix (EEFM) selective catalytic oxidation (SCO) tubular fixed-bedreactor (TFBR) 

摘      要：This work describes the environmentally friendly technology for oxidation of ammonia （NH3） to form nitrogen at temperatures range from 423K to 673K by selective catalytic oxidation （SCO） over a nanosized Pt- Rh/γ-A12O3 catalyst prepared by the incipient wetness impregnation method of hexachloroplatinic acid （H2PtC16） and rhodium （Ⅲ） nitrate （Rh（NO3）3） with γ-A12O3 in a tubular fixed-bed flow quartz reactor （TFBR）. The characterization of catalysts were thoroughly measured using transmission electron microscopy （TEM）, three- dimensional excitation-emission fluorescent matrix （EEFM） spectroscopy, UV-Vis absorption, dynamic light- scattering （DLS）, zeta potential meter, and cyclic voltam- metry （CV）. The results demonstrated that at a temperature of 673K and an oxygen content of4%, approximately 99% of the NH3 was removed by catalytic oxidation over the nanosized Pt-Rh/γ-A12O3 catalyst. N2 was the main product in NH3-SCO process. Further, it reveals that the oxidation of NH3 was proceeds by the over-oxidation of NH3 into NO, which was conversely reacted with the NH3 to yield N2. Therefore, the application ofnanosized Pt-Rh/γ-A12O3 catalyst can significantly enhance the catalytic activity toward NH3 oxidation. One fluorescent peak for fresh catalyst was different with that of exhausted catalyst. It indicates that EEFM spectroscopy was proven to be an appropriate and effective method to characterize the Pt clusters in intrinsic emission from nanosized Pt-Rh/γ-A12O3 catalyst. Results obtained from the CV may explain the significant catalytic activity of the catalysts.