应用傅立叶变换红外光谱仪研究煤在氧化自燃中不同温度所生成的气体产物。在30℃~100℃左右有水和二氧化碳气体析出,温度升至105℃~150℃左右时,有一氧化碳生成。采用密度泛函B3LYP法,在6-311G基组水平上研究煤与氧发生自燃反应生成水和一氧化碳的反应体系,对反应势能面上各驻点的几何构型全优化,用频率分析法和内禀反应坐标(IRC)法验证过渡态。计算结果表明,煤自燃生成一氧化碳的反应是氧分子攻击苯环侧链上丙基末端的碳原子,使丙基生成带醛的基团(-CH2-CH2-CO—H)和水,而带醛的基团继续分解生成一氧化碳。由反应活化能可知,生成水和一氧化碳的反应是一个自发式反应。
The gaseous produce in the process of coal oxidized spontaneous combustion under different temperature has been studied by the FTT spectroscope experiment. When the temperature rises to about 30℃- 100℃ water and carbon dioxide gas separated out, about 105℃ -150℃, carbon monoxide has been produced. Using the DFT B3LYP method, we studied the reaction system of the coal and the oxygen having the spontaneous combustion reaction and producing water and carbon monoxide in the 6-311G base group level, and have carried on optimization of all stagnation points geometry configuration on reaction potential energy surface, with the frequency anal- ysis method and the IRC method had carried on confirmation to the transient formation. The calculation results indicate that the reaction of coal spontaneous combustion producing carbon monoxide is the oxygen molecule attacks the carbon atom in the propyl group terminal on the benzene ring side chain, which causes the propyl group on the benzene ring side chain to produce the containing aldehyde group ( -CH2-CH2-COH ) and the water, and the containing aldehyde group continues breaking up into carbon monoxide. The reaction of producing water and carbon monoxide is a spontaneous reaction judging by the reaction activation energy.