无烟煤微晶结构的高分辨率透射电镜分析

High resolution TEM image analysis of anthracite coal microcrystalline structure

对阳泉3号无烟煤4张HRTEM图像的条纹长度、取向和堆垛分布进行了定量表征。结果表明,条纹分布特征均符合无烟煤的煤级特点。对图片1中3个不同微晶结构区域的条纹进行统计,结果表明,1号区域中,晶格条纹较短平均长度为0.87 nm,整体条纹取向分布杂乱,但短条纹之间以及长条纹之间仍各自存在小范围的有序排列,堆垛最大层数仅4层;3号条纹区域中,晶格条纹较长平均为1.01 nm,取向在135°−180°有较高富集,比例达62.46%,同时堆垛最大层数可达到6层;2号区域条纹分布特征则介于1号和3号之间。大部分条纹表现出弯曲的形态,可能其中有杂元环以及脂肪环的存在。FT-IR和^(13)C NMR的数据表明,脂肪结构多以脂肪环形式存在,其在短条纹拼接形成长条纹的过程中发挥着重要作用。

Four HRTEM images of Yangquan No.3 anthracite were quantitatively characterized,including fringe length,orientation and stacking distribution.The result indicates that the fringe characteristics are consistent with the coal rank characteristics of anthracite.The fringe of three different microcrystalline regions in image 1 was statistically analyzed.In region 1,the average fringe length is 0.87 nm,the overall fringe orientation distribution is disorderly,but there is still a small range of orderly arrangement between the short fringes and between the long fringes,and the maximum number of stacking layers is 4;In region 3,the fringe length is 1.01 nm on average,the orientation is higher in the range of 135°−180°with a ratio of 62.46%,and the maximum number of stacking layers can reach 6.The fringe distribution characteristic of region 2 is between 1 and 3.Most of the fringes are curved,and there may be heterocyclic rings and aliphatic rings.The FT-IR and ^(13)C NMR data show that the aliphatic structure mainly exists in the form of aliphatic rings,which plays an important role in the process of forming long fringes by short fringes.