煤沥青中甲苯可溶物的基础物性研究

摘要

以甲苯为萃取剂分别对中温沥青 (MP) 、氧化改性沥青 (OMP) 和热缩聚改性沥青 (TMP) 进行溶剂萃取-热过滤-蒸馏处理, 得到三种甲苯可溶物 (依次命名为TS1M、TSOM和TSTM) .利用元素分析仪、GPC凝胶渗透色谱、H-NMR、FTIR结合分峰拟合的方法对三种甲苯可溶物的芳香性指数 (Iar) 、支链化指数 (CH3/CH2) 和芳香缩合度 (fa) 等基础性质进行了计算研究, 利用TGA热分析仪对甲苯可溶物的热解行为进行了研究, 并且利用SEM、偏光显微镜 (PM) 对热解产物的微观结构进行了观察.结果表明:TSM、TSOM和TSTM三种甲苯可溶物的芳香性极佳, Iar指数分别为0. 949、0. 954和0. 987, fa指数依次为0. 967 2、0. 968 7和0. 978 5.TSM、TSOM和TSTM的CH3/CH2指数依次为0. 200、0. 297和0. 503, 说明三种甲苯可溶物的支链数量和支链长度依次减少.TSM、TSOM和TSTM的热解特征温度依次升高, 与三种甲苯可溶物中Iar、fa和CH3/CH2的指标相关联.%Three kinds of toluene soluble (named as TSM, TSOMand TSTM) were obtained via the method of solvent extraction-hot filtering-distillation, and using toluene as solvent, medium pitch (MP) , oxidation modified pitch (OMP) and thermal modified pitch (TMP) as raw materials.Elemental analyzer GPC gel permeation chromatography, 1 H-NMR, and FTIR spectroscopy combined with curve-fitting method were employed to study the basic properties of the resultant toluene solubles, such as aromatic index (Iar) , branching index (CH3/CH2) and aromatic condensation (fa) . Moreover, TGA analyzer was used to reveal the thermostability of the toluene soluble, SEM and polarizing microscope (PM) was used to observe the micro-structure of the pyrolysis products. The experimental results indicated the satisfactory aromaticity of all the three kinds of toluene solubles, as the aromatic indices (Iar) of TSM, TSOM, and TSTMare 0. 949, 0. 954 and 0. 987, respectively. The aromatic condensations (fa) are 0. 967 2, 0. 968 7 and 0. 978 5, respectively. The branching indices (CH3/CH2) of TSM, TSOM, and TSTMare 0. 200, 0. 297 and0. 503. It means that the number and the length of the branched chain in these three samples are in descending order. The pyrolysis characteristic temperature of TSM, TSOM, and TSTMwere increased successively, which is correlated well with the indicators of Iar, CH3/CH2 and fa.