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摘要: 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 13C 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。Abstract: 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 13C 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.
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Key words:
- HRTEM /
- anthracite coal /
- lattice fringe /
- microcrystalline structure
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图 10 不同区域短、中、长条纹长度假色晶格条纹图像
Figure 10 Short, medium, and long fringes false-colored by length of different regions
(a1), (b1), (c1) total fringes of region 1, 2, and 3; (a2), (b2), (c2) short fringes of region 1, 2, and 3; (a3), (b3), (c3) medium fringes of region 1, 2, and 3; (a4), (b4), (c4) long fringes of region 1, 2, and 3
表 1 样品的工业元素分析及镜质组反射率
Table 1 Proximate and ultimate analyses, vitrinite reflectance of coal sample
Sample Proximate
analysis w/%Ultimately
analysis wdaf/%Ro, max/% Mad Aad Vdaf C H O N S YQ-3 0.95 10.88 9.90 91.72 3.79 2.71 1.34 0.44 2.59 表 2 煤样的 13C NMR结构参数
Table 2 Structural parameters derived from 13C NMR spectrum of coal sample
Sample fa fac fa’ faH faN faB faS faP fal fal* falH falO YQ-3 0.93 0.02 0.91 0.53 0.38 0.24 0.12 0.02 0.07 0.01 0.03 0.03 note: fa-total sp2 hybridized C; fal-total sp3 hybridized C; fac -carbonyl group or carboxyl group C; fa’-aromatic C; faH-protonated and aromatic C; faN -non-protonated and aromatic C; faP-aromatic C bonded to hydroxyl or ether oxygen (δ = 150−165); faS -alkylated aromatic C; faB - aromatic bridgehead C; fal*-CH3 or quaternary C; falH -CH or CH2; falO-aliphatic C bonded to oxygen 表 3 六边形芳香片层长度参数
Table 3 Length parameters of hexagonal-shaped aromatic layers
C number Min L/nm Max L/nm Mean L/nm Benzene 0.246 0.284 0.265 Naphthalene 0.284 0.492 0.388 C13 0.492 0.497 0.495 C24 0.710 0.738 0.724 C27 0.738 0.923 0.831 C37 0.923 0.984 0.954 C54 1.136 1.230 1.183 C80 1.476 1.610 1.543 C96 1.540 1.704 1.622 表 4 每15°范围内的条纹分布
Table 4 Distribution of fringe within 15° bins
Angle/(°) Distribution of fringes/% region 1 region 2 region 3 0−45 24.23 18.09 25.59 45−90 16.04 6.48 2.66 90−135 24.91 18.43 9.30 135−180 34.81 56.99 62.46 -
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