煤焦油及其组分在超临界水中的反应特性研究

采用间歇超临界水（supercritical water, SCW）反应器，考察了三种煤焦油及其组分在SCW中的反应性。实验结果表明，沥青质裂解活性高的煤焦油在SCW中反应，轻质产物多，轻质化效果好。沥青质是轻质化反应的主要组分，它发生两极分化反应生成轻油和残焦。与常压N2热解相比，SCW可以促进沥青质转化为轻油并抑制缩合成焦的反应。由沥青质组分反应产物推断，煤焦油沥青质的芳香核主要是由1~4环的芳香族化合物构成。轻油组分在SCW中较为稳定，不足10%的轻油转化为沥青质和残焦。残焦组分在SCW中不发生反应。基于各组分的反应，探讨了煤焦油组分在SCW中的反应路径。

Reaction property of coal tar and its fractions in supercritical water

Conversions of 3 coal tars and their fractions in supercritical water (SCW) were investigated using a batch reactor. The results indicate that the conversion of the coal tar which has the highest content of asphaltene can obtain more light product compared with the other two coal tars. It is also noticed that asphaltene is the main active component and it converts to maltene, gas and char in SCW. Compared with pyrolysis in N2, the conversion of asphaltene to maltene is enhanced while the formation of gas and char is restrained in SCW. Based on analysis of pyrolysis product, it is deduced that aromatic nucleus of asphaltene molecule is mainly composed of 1～4 rings aromatic compounds. Moreover, less than 10% of maltene fraction converts to gas, asphaltene and char. The fraction of char is very stable in SCW. Reaction pathway of coal tar in SCW is proposed from the reaction property of each fraction.