Abstract In this study, chemical structure and pyrolysis reactivity of six different coal particle fractions were researched using Fourier transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA), respectively. An on-line FTIR was applied to assess the evolution characteristics of the gaseous products. The results expose that with the particle size decreasing, the ash content of Shenmu coal sample gradually increases, while the pyrolysis reactivity steadily decreases. In addition, the content of hydrogen as well as some typical chemical groups in coal is also affected by particle size. In our experimental conditions, the comprehensive infrared structural parameter has a good linear relation with pyrolysis reactivity. Moreover, with the particle size decreasing, the release amount of CH4, aliphatic hydrocarbons and light aromatic hydrocarbons gradually decreases, while the release amount of CO changes little.

中文翻译：

---

不同粒径神木煤化学结构、热解反应性及气态产物评价

摘要 本研究分别利用傅里叶变换红外光谱(FT-IR) 和热重分析(TGA) 研究了六种不同煤颗粒组分的化学结构和热解反应活性。应用在线 FTIR 来评估气态产物的演化特征。结果表明，随着粒径的减小，神木煤样品的灰分含量逐渐增加，而热解反应活性逐渐降低。此外，煤中氢的含量以及一些典型的化学基团也受粒度的影响。在我们的实验条件下，综合红外结构参数与热解反应性具有良好的线性关系。此外，随着粒径的减小，CH4 的释放量、