Abstract:

The pyrolysis reactivity of demineralized higher rank coal loaded with Fe₂O₃ by using co-mixing was investigated with thermo-gravimetric analyzer, and it was indicated that pyrolysis reactivity of the sample loaded with Fe₂O₃ was higher than that of the sample without Fe₂O₃.Chars were prepared from the two coal samples in a temperature programmed muffle furnace, and their structures were analyzed by using FTIR, XRD and RAMAN.TG and FTIR results showed an increase of pyrolysis conversion and free radicals during pyrolysis of demineralized coal with Fe₂O₃.XRD revealed that diffraction angle of 002 peak did not change obviously, while by contrast, L_a and L_c decreased by loading with Fe₂O₃, indicating decreasing degree of graphitization for microcrystalline structure of char.In addition, parts of Fe₂O₃ were reduced to FeO as shown in XRD.RAMAN spectroscopy showed decreasing area of G band and increasing area of D band for char from demineralized anthracite loaded with Fe₂O₃, indicating that ordering of char was decreased by Fe₂O₃.

Key words:

高变质程度, 催化热解, 半焦, 结构

摘要：

利用热天平研究了共混合法负载Fe₂O₃高变质程度脱灰煤的热解反应性，结果表明煤粉负载Fe₂O₃后热解反应性高于无负载的热解反应性。负载Fe₂O₃煤样在程序升温加热的马弗炉中制备出半焦，利用FTIR、XRD和RAMAN 等分析了半焦结构。由TG和FTIR可知，负载Fe₂O₃煤样热解时，热解转化率增加，热解后自由基增加。由XRD可知，Fe₂O₃没有使得煤样半焦的002峰衍射角发生明显变化，但使L_a和L_c参数明显降低，说明半焦的微晶结构石墨化程度降低。另外，在XRD分析谱图中发现部分Fe₂O₃被还原成FeO。由RAMAN可知，Fe₂O₃使半焦的G峰峰面积降低，D峰峰面积增加，说明半焦的有机结构有序化程度降低。

关键词:

高变质程度, 催化热解, 半焦, 结构