摘要:As an important precursor of ozone and haze, volatile organic compounds (VOCs) have been attracting high attention in the field of energy and environment. In this paper, active species reactions and bond energy effects in the process of VOCs degradation by plasma were illustrated, then bond breakage- combination rules (B-C rules) were created and used to interpret intermediate products and their formation pathways by using Chemdraw software, and the types and toxicity of by-products were analyzed as well. Taking toluene as the VOCs representative, the results showed that in the process of plasma degradation of toluene, the by-products formation pathway conformed to the B-C rules, the C-C bond between the benzene ring and the methyl group was broken firstly, and then the by-product phenyl radical combined w ith other radicals toform new intermediate products, such as benzaldehyde, phenol, benzoic acid, nitrobenzene, etc. After the addition of the catalysts into plasma system, the formation of beneficial free radicals for VOCs degradation were promoted, which helped boost the energy of the plasma, and the intermediate products were further converted into alkanes, 2-methylbutane, acetaldehyde, formic acid, benzoic acid, benzaldehyde, benzyl alcohol, 3- methyldiphenyl ketone and so on, which eventually were degraded into water and carbon dioxide. The intermediates produced by the VOCs degradation can be classified into heavy toxicity, moderate toxicity and light toxicity substances depending on the toxicity.