【作者】 陈红；

【导师】 葛岭梅；

【作者基本信息】 西安科技大学 ， 矿物加工工程， 2009， 博士

【摘要】 煤的组成、结构及其反应性一直是煤科学中的一个很重要的基础问题,本论文通过对煤的溶剂抽提实验与抽提机理及动力学研究,加深了对煤组成和结构的理解。不同煤种因成煤植物和成煤环境等的不同,造成其组成和结构的差别。论文中以神府煤（SF）为主要研究对象,同时对华亭（HT）、铜川（TC）、伊泰（YT）、攀枝花（PZH）等四种煤进行了考察,以不同溶剂借助微波方法,研究了不同实验条件下煤的抽提结果。利用色质联用技术分析了煤抽提物组成,利用元素分析、傅立叶红外光谱和¹³C固体核磁共振波谱等现代测试技术分析了原煤、抽提残煤的结构及变化,并采用分峰拟合的方法计算了相关的煤结构参数如f_a、f_a^c、f_al等。比较神府煤的微波辅助抽提与传统索氏抽提的结果,微波辅助抽提在较短的时间内获得了较高的抽提率,且抽提物中化合物种类多于索氏抽提物。运用红外光谱分析及¹³C固体核磁共振分析量化研究了神府煤羟基官能团及氧接脂碳、季碳等参数的变化,利用Fick扩散定律,采用最小二乘法对微波辅助溶剂抽提煤进行了动力学分析,结果显示可用以脂肪烃、芳香烃化合物溶解为主和含杂原子化合物溶解为主的两阶段化学动力学方程描述。微波辅助下抽提温度、时间和溶剂的改变及煤中的矿物质对抽提率和抽提物组成都有影响。温度过高或过低都不利于杂原子化合物的溶出;随着抽提时间的延长,抽提率增大,但煤抽提物中脂肪族和芳香族化合物种类都有减少。变质程度相似的煤在相同的抽提条件下抽提率及抽提物族组成含量都有所差别;变质程度较高的攀枝花煤抽提物中前沥青烯的百分含量分别高于相同溶剂的其他四种煤抽提物中前沥青烯的百分含量。微波辅助条件下复合溶剂、分级抽提对神府煤都具有较好的溶解能力且抽提物组成也有一定的改变;表面活性剂有助于单一溶剂抽提率的提高,同时也会改变单一溶剂抽提物的组成;甲醇和乙醇溶剂中加入少量的路易斯酸后与单一溶剂抽提物相比抽提物相对集中,烷烃和芳烃化合物种类虽有减少,但两种溶剂的抽提率都有大幅度的提高。利用测试得到的煤分子结构官能团组成及计算出的相关结构参数如芳香度、脂肪碳等自建了分子碎片库,借助于混合遗传算法模拟了神府煤的大分子结构片段,实现了神府煤大分子结构模型的构建;模拟得到的神府煤分子结构片段的有关参数与实际煤样的测试分析数据十分接近,从而为我们从分子水平上了解神府煤的结构、性质与转化过程提供了依据和信息。更多还原

【Abstract】 The composition,structure and reactivity of coal have been a very important issue in coal science, complete understanding of coal composition and associated force between molecule can be accomplished by experiments of the solvent extracting coal and study on extraction mechanism and extraction kinetics in thesis. The difference in composition and structure between different coals is because of the diverse plants and exterior conditions during forming coals. The thesis takes five coals such as Shenfu coal,Huating coal,Tongchuan coal,Yitai coal and Panzhihua coal with different rank as its research objective and Shenfu coal is the primary objective to reveal the extract component, residual structure using different solvents under microwave-assisted extraction. Extracts and residues are analyzed with GC/MS and elemental analysis,FT-IR analysis, ¹³C-NMR analysis respectively. Relative structure parameters,for example, f_a, f_a^c, f_al are calculated by curve-fitting method.Different extraction methods lead to differ extraction yields and extract components. Comparison of microwave-assisted extraction and Soxhlet extraction,there was a higher extraction yield of microwave-assisted extraction than that of Soxhlet extraction and there were more organic compounds in extracts of microwave-assisted extraction than that of Soxhlet extraction during shorter time. FT-IR and ¹³C-NMR analyses are employed to quantitatively calculate hydroxy functional group and f_al^o, f_al^H of Shenfu coal and its residues. Fick diffusion law using least square method calculates microwave-assisted extraction kinetics equation and the process of microwave-assisted extraction is divided into two stages in which aliphatic and aromatic compounds are dissolved mostly and compounds containing heteroatoms are dissolved mostly respectively.Furthermore,the experimental results reveal that different extraction temperature,extraction time, solvents and minerals in coals affecting extraction yields and extract components. Higher and lower temperature are not in favor of extraction compounds containing heteroatoms;Extraction yields increase when the extraction time is extended,which leads to decrease of aliphatic and aromatic compounds in extract.Results of study on coals with similar rank reveal that extraction yields and extract component contents are different under the same extraction conditions. The percent content of preasphaltene fraction of extracts in higher rank Panzhihua coal is higher than that of in Yitai,Tongchuan,Huating and Shenfu coals under the same conditions.Microwave-assisted extraction of Shenfu coal experimental results show that Shenfu coal is dissolved well by composite sovents and fractionation extraction experiment and extract components are also changed. Experimental research shows that surfactants are benefit to improve the single solvent extraction yields and influence extract components; A few Lewis acid such as Ferric chloride and Zinc chloride are also benefit to largely increase the extraction yields of methanol and alcohol. Although species of alkanes and arenes in extracts of containing additives are less than that of in single solvent, which leads to the relative concentration of extracts.Shenfu coal macromolecular fragment model is assembled using a self-adaptive genetic algorithm by self-build molecular fragement base from the different functional groups and relative structural parameters such as f_a , f_al. A large and complicated coal structural model is constructed. Simulated value of relative parameters are quite close to test value, which supplies worth information on understanding structure, character and conversion from the point of view of molecule structure.更多还原