The Effects of Cr-Substitution in Ferrite Catalysts and the Catalytic Dehydrogenation of Ethylbenzene

페라이트 촉매의 Cr 치환효과와 에틸벤젠의 탈수소반응

  • Lim, Ki-Chul (Science and Technology Policy Institute) ;
  • Kim, Eul-San (Department of Chemistry, Korea Military Academy) ;
  • Lee, Ho-In (Department of Chemical Technology, Seoul National University)
  • Received : 1991.06.22
  • Published : 1991.09.30

Abstract

Mg- and Zn-ferrites having spinel structure, a kind of complex oxides showing the advantageous properties of constituent single metal oxides, were selected to find a relationship between their catalytic activities in the dehydrogenation of ethylbenzene to styrene and the catalytic properties. For the structural and physical analyses of ferrites, XRD, BET, TG/DTA, ESCA, TEM, and TPD methods were employed. The effects of Cr-substitution were intensively studied by the experimental methods mentioned above. Chromium which showed a preferential tendency to diffuse to the surface acted as a structural promoter by increasing surface area and stability of catalyst structure. In the dehydrogenation of ethylbenzene, catalytic activity, and the effects of Cr-substitution were investigated. Oxygen mobility was decreased with the amount of Cr-substitution in $MgCr_xFe_{2-x}O_4$, which resulted in the increase of selectivity to styrene and the suppression of total oxidation.

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Acknowledgement

Supported by : 육군사관학교