煤中芳核侧链模型化合物丁基蒽的初次热解

Initial pyrolysis mechanism of aliphatic group on aromatic cluster in coal structure by using butyl anthracene as model compound

利用Gaussian 03程序包中的DFT/B3LYP方法,在6-311G基组上对煤的模型化合物正丁基蒽烷基侧链热解机理进行了研究,计算了不同温度下各反应路径的热力学参数及产物自由基的前线轨道能级差。结果表明:正丁基侧链上最容易发生的反应是β位C—C键的断裂;在正丁基蒽的3个同分异构体中连在γ位的侧链反应活性最高;芳环尺寸对烷基侧链的β位C—C键有一定的影响,但对其他C—C键影响不大。

The pyrolysis mechanism of alkyl side chain of n-butyl anthracene as model compound of coal was studied by using the DFT/B3LYP/6-311G method in the Gaussian program package. The thermodynamic parameters of all reaction processes and the frontier orbital energy difference of the product free radical were calculated. The results indicated that the β C-C bond dissociation in the alkyl side chain of n-butyl anthracene was the easiest to occur. In the three isomeric hydrocarbons of n-butyl anthracene the alkyl side chain connected to the 7/C atom had the highest reactivity. The size of aromatic rings had positive effect on the βC-C bond dissociation of the alkyl side chain, but had only a little effect on the other C-C bonds.