Characterizations of aggregation states of coal soluble constituents at solid state
Characterizations of aggregation states of coal soluble constituents at solid state
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DOI：
10.1021/ef010162w
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发表时间：
2002
期刊：
影响因子：
5.3
通讯作者：
H. Shui;K. Norinaga;M. Iino
中科院分区：
文献类型：
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作者：
H. Shui;K. Norinaga;M. Iino
获得了三种在NMP中具有不同溶解度的煤提取物的吡啶不溶组分(PI)。原始PI（PI-0）是用二硫化碳/N-甲基-2-吡咯烷酮（CS2/NMP）混合溶剂（体积比1:1）对Upper Freeport（UF）煤提取物进行吡啶分馏而得到的，在室温下在NMP中的溶解度为53wt%。通过添加少量的乙酸四丁基铵 (TBAA)，PI-0 几乎完全溶解在 NMP 中。 PI-1是通过将PI-0溶液在含有TBAA的NMP中去除NMP和TBAA而得到的，其在NMP中的溶解度为98wt％。而PI-2是由PI-1溶液在不含TBAA的NMP中脱溶剂得到的，其在NMP中的溶解度为48wt％。采用差示扫描量热法 (DSC) 和热机械分析 (TMA) 来表征这三种固体 PI 的聚集状态。结果证实，三种PI溶解度的差异归因于它们不同的聚集状态。与 PI-0 或 PI-2 相比，PI-1 具有较少的聚集结构，因为它是通过 NMP 与 TBAA 蒸发而获得的，TBAA 起到煤分子聚集抑制剂的作用。
Three kinds of pyridine-insoluble fractions (PI) of coal extracts with different solubility in NMP were obtained. Original PI (PI-0), which was obtained by pyridine fractionation of Upper Freeport (UF) coal extracts with carbon disulfide/N-methyl-2-pyrrolidinone (CS2/NMP) mixed solvent (1:1 by volume), has 53 wt % of solubility in NMP at room temperature. By the addition of a small amount of tetrabutylammonium acetate (TBAA), PI-0 became almost completely soluble in NMP. PI-1 was obtained by the removal of NMP and TBAA from PI-0 solution in NMP containing TBAA, and it has 98 wt % of solubility in NMP. While, PI-2 was obtained from the solvent removal of PI-1 solution in NMP without TBAA, and it has 48 wt % of solublility in NMP. Differential scanning calorimetry (DSC) and thermomechanical analysis (TMA) were employed to characterize the aggregation states of these three solid PIs. The results confirm that the difference in the solubilities of the three PIs was attributed to their different aggregation states. PI-1 has a less aggregated structure compared to PI-0 or PI-2, because it was obtained by the evaporation of NMP with TBAA, which acts as an inhibitor of the aggregation of coal molecules.