The adsorption of dioxin–modeling compounds on activated carbon has been investigated in this
manuscript. A series of benzene compounds with different numbers and types of substituent groups were
chosen as the dioxin–modeling compounds, and the gas adsorption behaviors were evaluated using a
fixed-bed reactor. The adsorption results showed that the methyl, chlorine and phenolic substituent
groups on a benzene ring can greatly promote gas adsorption, especially the phenolic group, the addition
of which increased the adsorption capacity to more than 1.5 times that of benzene. The adsorbed AC samples
were detected by TPD-MS with the combines between adsorbate and adsorbent analyzed, the methyl
and chlorine groups enhanced the attraction between the gaseous compounds and AC, while the phenolic
group reduced the combine force due to its oxidation on AC. The effect of an increasing number of
chlorine substituents on the adsorption of gases and the combine forces were investigated. On average,
the capacity of gas adsorption doubled and the desorption temperature increased by 20 K with one
chlorine substituent on a benzene ring. The attachment of chlorine substituent groups to the AC lactone
and quinone groups has been verified again, and the increasing chloric substituent groups consumed
more oxygen groups. According to the linear relationships between gas properties and adsorption behaviors,
the actual dioxin adsorption capacity has been inferred to be 600 mg/g or greater, showing that
dioxin is much more easily adsorbed on AC than the conventional organic gases.