The Effects of Sulfur on the Catalytic Reaction between Carbon Monoxide and Nitric Oxide on Polycrystalline Platinum Surface

다결정 백금표면에서의 일산화탄소와 일산화질소의 촉매반응에 미치는 황의 영향

  • Park, Youn-Seok (Samsung General Chemicals Research Center) ;
  • Kim, Young-Ho (Department of Chemical Technology, Seoul National University) ;
  • Lee, Ho-In (Department of Chemical Technology, Seoul National University)
  • 박윤석 (삼성종합화학 연구소) ;
  • 김영호 (서울대학교 공과대학 공업화학과) ;
  • 이호인 (서울대학교 공과대학 공업화학과)
  • Received : 1990.11.30
  • Published : 1990.12.31

Abstract

The effects of sulfur on the catalytic reaction between CO and NO on polycrystalline Pt surface, which is very important in the development of catalyst for automobile exhaust gas control, have been studied using thermal desorption spectrometry(TDS) under ultra-high vacuum(UHV) conditions. Sulfur weakened both the adsorptions of CO and NO by direct site blocking and indirect electronic effect. S(a) desorbing below 800 K gave little effect on reaction activity whereas S(a) desorbing above 800 K, which adsorbs as an atomic state, gave much effect on it. The adsorbed sulfur existed on the surface of platinum in the form of islands, and also reduced the adsorption energies of adsorbates by the long-ranged electronic effect. The platinum catalyst in the reaction between CO and NO was poisoned selectively by S(a), poisoning firstly the active sites of this reaction.

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Acknowledgement

Supported by : 서울대학교