화학공학소재연구정보센터
Applied Chemistry for Engineering, Vol.27, No.1, 56-61, February, 2016
천연 광물질을 이용한 CO2 석탄 촉매 가스화 반응 특성 연구
Study on CO2-Coal Gasification Reaction Using Natural Mineral Catalysts
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초록
본 연구에서는 천연 광물질 촉매를 사용하여 CO2 석탄가스화의 반응특성을 조사하였다. Meng Tai지역의 갈탄에 4종류의 천연 광물질(Dolomite, Silica sand, Olivine, Kaolin)을 각각 5 wt%로 물리적으로 혼합한 후 Thermogravimetric Analyzer (TGA)를 이용하여 800, 850, 900 ℃에서 CO2 가스화 반응을 수행하였다. 실험 결과를 Volumetric Reaction Model (VRM), Shrinking Core Model (SCM), Modified Volumetric Reaction model (MVRM)을 이용하여 분석하였다. MVRM이 가장 적합하였다. 반응 온도가 올라감에 따라 반응속도상수가 커졌다. 천연 광물질 촉매를 사용할 경우가 촉매를 혼합하지 않은 경우에 비해 반응속도상수는 커지고 활성화 에너지 값이 낮아졌다. Silica sand를 혼합한 시료의 활성화 에너지 값은 114.90 kJ/mol로 가장 낮은 활성화 에너지 값을 보였다. Kaolin을 혼합한 시료의 경우 850 ℃와 900 ℃에서 각각 가장 높은 반응속도상수를 보여주다가 800 ℃에서 낮은 반응속도상수를 나타냈다. 따라서 Kaolin을 혼합한 경우, 반응 온도가 높아질수록 CO2 가스화에 좋은 효과가 있을 것이다.
In this study, the effect of natural minerals on the reaction kinetics for lignite-CO2 gasification was investigated. After physical mixing of lignite from Meng Tai area with 5 wt% of each natural mineral catalysts among Dolomite, Silica sand, Olivine and Kaolin, CO2 gasification was performed using TGA at each 800, 850 ℃ and 900 ℃. The experimental data was analyzed with volumetric reaction model (VRM), shrinking core model (SCM) and modified volumetric reaction model (MVRM). MVRM was the most suitable among three models. As increasing the reaction temperature, the reaction rate constant became higher. With natural mineral catalysts, the reaction rate constant was higher and activation energy was lower than that of without catalysts. The lowest activation energy, 114.90 kJ/mol was obtained with silica sand. The highest reaction rate constant at 850 ℃ and 900 ℃ and lower reaction rate constant at 800 ℃ were obtained with Kaolin. Conclusively, the better catalytic performance could be observed with Kaolin than that of using other catalysts when the reaction temperature increased.