先锋褐煤热溶及热溶物红外光谱表征

利用高温热溶装置研究了不同溶剂中先锋褐煤热溶性能，并对热溶物和热溶残煤分别进行了红外光谱表征。结果表明，先锋褐煤以化学交联大分子结构为主，非共价键缔合低分子化合物含量较低；虽然高温热溶可以显著提高热溶效率，300℃甲苯和四氢萘溶剂中热溶率达到20.7%和21.3%，但是以热断裂煤结构中的非共价键作用，促进低分子化合物溶解为主；300℃热溶过程中不存在明显热解反应，供氢溶剂及氢键型溶剂作用不明显；先锋褐煤热溶物中含有丰富的脂肪结构和羧酸酯，羟基和芳香结构含量较低；热溶溶剂明显影响热溶物结构与组成。

High temperature thermal extraction of Xianfeng lignite and FT-IR characterization of its extracts and residues

High-temperature thermal extraction (TE) of Xianfeng lignite by different solvents was carried out, and FT-IR spectra of extracts and residues were determined. The results indicate that Xianfeng lignite shows the macro-molecular network structure by chemical bond cross-linking, in which some low molecular compounds are associated by non-covalent interaction. The TE can distinctly increase the extraction yields, which are up to 20.7% and 21.3% at 300℃ in toluene and tetralin, respectively. The extracts result from the release of low molecular compounds by thermal rupture of non-covalent bonds at high temperature. Meanwhile, there is no obviously pyrolysis in the process of thermal extraction at 300℃. So the hydrogen donor solvent and hydrogen bond solvent can not increase the thermal extraction yield. The thermal extracts of Xianfeng lignite contain a great of aliphatic alkyl and carbonyl ester, a little of hydroxyl and aromatic structure. The solvent of thermal extraction shows distinctly influences on the constitution and structure of extracts.