富含半丝质体煤液化残渣的煤岩学特征和煤结构变化

The petrological features and chemical structure in liquefaction residues of coal rich in semi-fusinite

选择富含半丝质体煤为研究对象,在沙浴-管式反应器中进行了液化实验,通过光学显微镜分析了液化残渣的煤岩学特征,运用FT-IR、固态13C NMR和Py-GC/MS等分析测试手段对比研究了原煤和液化残渣的化学结构特征变化。结果表明,样品虽富含半丝质体,但其液化转化率达到50%以上。残渣的显微观察表明,半丝质体有软化、甚至表面呈空心状等特征变化,证明半丝质体参与了液化反应。对比分析FT-IR、固态13C NMR和Py-GC/MS图谱表明,在液化过程中,样品的化学结构特征发生了变化。Py-GC/MS分析表明,液化残渣的化学结构以烷基萘为主,且以C2-萘和C3-萘为主。并进一步结合理论和显微观察等多方面因素分析讨论了半丝质体在液化中的作用。

The coal rich in semi-fusinite was selected to run liquefaction rests in tubing-bomb reactors in a pre-heated sand bath. The petrological features of liquefaction residues were observed by microscopy, and the comparative discussion on chemical structure on raw coal and relatively liquefaction residues were presented by using FT-IR, 13 C-NMR, and Py-GC/MS techniques. The results show that the liquefaction conversion reaches to more than 50% although coal used with high semi-fusinite content. The optical examination of liquefaction residues show that the partial semi-fusinites become plastic, and even formes hollow spheres, which indicate that semi-fusinites have involved in the liquefaction reaction. The comparison of chemical structure of raw coal and relatively liquefaction residues clearly show that the changes of chemical structures during liquefaction are occurred. Furthermore, the results of Py-GC/MS show that the compounds in residue are mainly composed of alklynaphthalene, C2-naphthalene and C3-naphthalene are main consti- tutions. Finally, the role of semi-fusinite in liquefaction was further discussed according to the results of speculation and petrological features.