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Metallurgical and Materials Transactions B

, Volume 34, Issue 4, pp 433–437 | Cite as

Kinetics and mechanism of carbothermic reduction of magnesia

  • Li Rongti
  • Pan Wei
  • Masamichi Sano
Article

Abstract

The reaction between MgO and graphite powders under flowing argon atmosphere was studied using a dynamic thermogravimetric method. In the temperature range 293 to 1973 K, the effects of compacting pressure, magnesia/carbon ratio, heating rate, Ar carrier-gas flow rate, and CO-partial pressure were investigated. An experimentally determined reaction mechanism was proposed and discussed. The reduction process could be divided into two stages. The first stage includes the direct reaction between MgO and graphite particles and partial gas-solid reaction at relatively low temperature (below 1750 K). The overall reaction rate depends on the solid phase-boundary reaction between magnesia and carbon particles. The second stage is the gas-solid reaction between CO and MgO, which determines the overall reaction rate. The apparent activation energies of the two stages were estimated to be 208.29 and 374.13 kJ/mol, respectively.

Keywords

Material Transaction Carbon Particle Reduction Ratio Graphite Powder Carbothermic Reduction 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© ASM International & TMS-The Minerals, Metals and Materials Society 2003

Authors and Affiliations

  • Li Rongti
    • 1
  • Pan Wei
    • 1
  • Masamichi Sano
    • 2
  1. 1.the Department of Materials Science and EngineeringTsinghua UniversityBeijingPeople’s Republic of China
  2. 2.the Department of Materials Process Engineering, Graduate School of EngineeringNagoya UniversityAichi-kenJapan

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