煤化学 煤的族组成

1、part 4： coal constituents chapter 4 coal petrographic constituents; chapter 5 coal chemical constituents; chapter 6 coal family constituents;,一、煤的族组成的概念及研究方法 煤族组成的概念concept： 煤的族组成是指在一定条件下，对煤的分子结构没有破坏的情况下，进行分子分离separate/separation后得到的组成。通常利用的手段就是溶剂萃取solvent extraction，即通过对煤有一定溶解能力的溶剂进行萃取分离的过程。,chapte

2、r6 coal family constituents,二、煤溶剂萃取的概念 煤的溶剂萃取又称为煤的溶剂抽提 ，它是指使用溶剂在一定温度下溶解煤dissolving coal ，形成溶液solution，再经蒸发evaporation溶剂、提取煤中可溶物soluble material的操作过程。,chapter6 coal family constituents,三、煤溶剂萃取的溶剂 conventional solvents for coal extraction can be grouped into four general categories: 1) nonspecific sol

3、vents /普通溶剂 2) specific solvents/特殊溶剂 3) degrading solvents/降解溶剂 4) reactive solvents/反应性溶剂,chapter6 coal family constituents,1) nonspecific solvents /普通溶剂 nonspecific solvents extract a small amount (10%) of coal at temperatures up to about 100. the extract is thought to arise from the so-called re

4、sins and waxes which do not form a major part of the coal substance. ethanol 乙醇is an example of this solvent.,三、煤溶剂萃取的溶剂,4) reactive solvents /反应性溶剂 reactive solvents dissolve coal by active interaction. such solvents are usually hydrogen donors and their chemical composition is appreciably affected

5、 during the process. tetralin四氢化萘is an example of such a solvent.,三、煤溶剂萃取的溶剂,四、煤溶剂萃取的影响因素factors affecting coal extraction （1）溶剂的影响effect of solvent on coal extraction 一般认为，煤的溶剂萃取是通过溶剂扩散渗透diffusion and penetration交联键断裂rupture煤网络结构network structure打开有机质溶解dissolving的过程进行的。因此，能对这几个中间过程产生影响的试剂或操作均可以影响萃取率及萃取速率。,四、煤溶剂萃取的影响因素,（2）煤化程度rank的影响 碳含量小于86 %的煤，萃取率随c含量升高而增加； 碳含量大于86 %的煤，萃取率反而随c 含量增加而急剧下降; 一般以c 含量在86 %左右的煤萃取率最高。,四、煤溶剂萃取的影响因素,（3）煤岩组分petrological constituents的影响 壳质组exinite 镜质组vitrinite 惰质组inertinite,四、煤溶剂萃取的影响因素,（4）辅助手段assistant means对煤溶解性的影响 超声处理ultrasonic disposal：在煤-溶剂固液体系中能大大加快传统溶剂萃取