Abstract: In order to analyze the low wettability about the bituminous coal dust with medium metamorphic grade from the microscopic aspect, taking Zhaolou gas-fat coal in Juye coalfield as the example, the methods of nuclear magnetic resonance and X-ray photoelectron spectroscopy were utilized to achieve the microscopic molecular structures, and the molecular parameters' influence on the wettability was investigated. According to the experimental results, the aromatic degree of the coal dust in Zhaolou mine was 0.77, and the content of aromatic structure was large, which mainly contained protonated aromatic ring. Moreover, chain alkanes and cycloalkanes side chains held the most part of aliphatic chain structures, also some methyl side chains were included. Ether group (C—O—C) was the first superficial oxygen-containing functional group of coal dust in Zhaolou mine. The second was carbonyl (C=O). The third was hydroxy (C—OH). The last was carboxyl (COOH). Moreover, the content ratio of the above four groups was about 4:2:2:1.5. Not only the aromatic degree of the coal dust was high, the size of aromatic cluster was large and the condensation degree was high, but also the alkyl side chains were few and short, which made the coal's molecular structure unit shows a strong hydrophobicity. However, the carboxyl (COOH) and hydroxy (C—OH), which contributed much to the surface hydrophilicity, only held 13.53% and 21.45% of the whole content of superficial oxygen-containing functional groups, respectively. Therefore, influenced by microscopic molecular structures, the coal dust of Zhaolou mine showed an overall characteristic of hydrophobicity and poor wettability.

Key words: NMR, XPS, powder, chemical analysis, wettability

摘要： 为从微观角度分析中变质烟煤的低润湿特性，以巨野煤田赵楼气肥煤为例，选用核磁共振（NMR）与X射线光电子能谱（XPS）手段对其微观分子结构进行实验，并分析了分子结构参数对其润湿性的影响规律。结果表明，赵楼气肥煤煤尘的芳香度为0.77，芳香结构含量较高，且主要以质子化芳环为主；脂肪链结构中以链状烷烃和环烷烃侧链为主，且存在一定的甲基侧链；煤尘表面含氧官能团主要为醚基（C—O—C），其次为羰基（C=O）与羟基（C—OH），含量最少的是羧基（COOH），上述4种含氧官能团含量之比约为4∶2∶2∶1.5。赵楼气肥煤煤尘不仅芳香度较高，芳香簇尺寸较大，缩合度偏高，而且烷基侧链少而短，导致煤尘分子结构单元表现出较强的疏水性；而对表面亲水性贡献较大的羧基（COOH）和羟基（C—OH）含量却只占表面含氧官能团总量的13.53%、21.45%。因此，受微观分子结构的影响，赵楼气肥煤煤尘总体表现出疏水性的特点，润湿性较差。

关键词: 核磁共振, X射线光电子能谱, 粉体, 化学分析, 润湿性