Isotherm Coefficient for Benzene and Toluene Adsorption on Granular Activated Carbon for Preparation of Biobarrier

Abstract

Biobarrier combines the adsorption and biodegradation processes which are carried out simultaneously. This method can increase the rate of contaminant reduction, reduce contaminant toxicity and extend the life of activated carbon. This study aims to evaluate the characteristics of benzene and toluene adsorption on granular activated carbon (GAC). The ratio of adsorption in the expanded bed to the fixed bed determines the operating conditions in the benzene biodegradation process experiment. The results showed that the GAC was distributed in the micropore and mesopore regions with a pore diameter of 15 Å to 23 Å. The molecular diameters for benzene and toluene are 5.285 Å and 5.72 Å, respectively, which fit the pores. The adsorption capacity of activated carbon can be represented well using the Freundlich equation. Freundlich’s constants for benzene and toluene are Kf = 17.87 (1/n = 0.46) and Kf = 25.88 (1/n = 0.45).