羟基自由基与典型苯系物的后续反应机理研究

Study on the subsequent reaction mechanism of hydroxyl radical and typical benzene series

为了研究大气中羟基自由基(·OH)氧化降解典型苯系物的反应机理.本文采用MPWB1K计算方法,理论上预测·OH与3种苯系物(苯、甲苯和对二甲苯)的反应过程,并全面地考虑了苯与·OH反应生成的加成和脱氢产物在大气中可能进行的后续反应机理及氧化降解产物.结果表明:·OH与苯、甲苯及对二甲苯的加成反应均比氢原子提取过程更容易发生,并且乙二醛、苯酚和硝基苯等是·OH氧化降解苯的主要产物,这对大气中二次有机气溶胶的形成有一定的贡献.

In order to study the reaction mechanisms of oxidative degradation of benzene series compounds caused by hydroxyl radicals(·OH)in the atmosphere.This paper uses the MPWB1K calculation method to theo⁃retically predict the primary reaction processes of·OH and benzene series(benzene,toluene and p⁃xylene),and comprehensively considers the possible follow⁃up reaction mechanisms and oxidative degradation outcomes of the addition and dehydrogenation products formed by the reaction of benzene and·OH in the troposphere.The results show that the addition reaction of·OH with benzene,toluene and p⁃xylene is easier to occur than the H atom ex⁃traction process,and glyoxal,phenol and nitrobenzene are the main products of oxidative degradation of benzene by·OH.The result has a certain contribution to the formation of secondary organic aerosols in the ambient atmo⁃sphere.