Oxidation of Ash Free Coal from Lignite and Anthracite Coals in a Molten Carbonate Fuel Cell

갈탄과 무연탄으로부터의 초청정석탄 제조 및 용융탄산염형 연료전지에서의 산화거동연구


  • Received : 2015.11.30
  • Accepted : 2016.02.28
  • Published : 2016.02.29


In this study, ash free coals(AFCs) were produced with lignite and anthracite coals in a microwave. The AFCs were analyzed with proximate analysis, fourier transform infrared spectrometry (FTIR), X-ray diffraction analysis, and thermogravimetric analysis (TGA). The extraction yields of the AFCs were 16.4 wt%, 7.6 wt% at lignite and anthracite coal, respectively. The chemical and physical properties of the AFCs were similar regardless of the original coal types. Oxidation behavior of the AFCs was investigated by supplying a mixture of 3g of AFC and 3g of electrolyte into the coin-type molten carbonate fuel cell (MCFC). For the evaluation of AFC fuel performance, electrochemical analysis of the steady-state polarization and step-chronopotentiometry were conducted based on the standard hydrogen fuel (69 mol% $H_2$, 17 mol% $CO_2$, 14 mol% $H_2O$). The AFCs showed similar electrochemical oxidation behaviors regardless of the original coal types. The overvoltage of the AFCs was larger than the hydrogen fuel, although OCV of the AFCs was higher.


Ash free coal;Solvent extraction;Lignite;Anthracite coal;Molten carbonate fuel cell


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