The Study On Mechanism Of The Low Temperature Oxidation Of Simulated Coal Molecule

Coal is an abundant natural resource in China, which accounted for more than 2/3 of the total energy in recent years. While spontaneous combustion of coal is one of the big disaster in the coal product. Every year the country put lots of money, financial to prevent the spontaneous combustion of coal seams. So to study the basic mechanism of the spontaneous combustion of coal is very important. Nowadays the oxidation of coal study is well recognized among the so many coal spontaneous combustion. Scholar study the mechanism from different point, such as study the activation energy, study the coal molecular structure model, study the surface reaction enthalpy, study infrared technique and detect spontaneous combustion in coal seams by isotope niton, etc. With the developing of computer technique, quantum chemistry expands faster. This makes it possible to study the reaction mechanism of coal molecular from microcosmic. This article simulates the oxidation of the coal molecule with benzene and some active groups on the surface at low temperature by using B3LYP/6-31G calculations. We use model complicated aromatic structures with a single phenyl to investigate the mechanism of coal oxidation at room temperature. It is proved that this method is available. The optimized geometries of reactants, transition state and products in the coal-oxygen reactions are found. Based on these optimized structures we obtain the reaction enthalpy, Gibbs free energy and the activation energy, etc., which should be helpful to understand the microcosmic mechanism of the low temperature oxidation of the nine simulated coal molecules.