Paper Title
Treatment of Benzene �Toluene Mixture in a Biofilter Using A Mixed Microbial Culture

Abstract
Biofiltration of benzene-toluene gas mixtures was investigated in a biofilter operated in an up-flow mode using mixed microbial cultures immobilized in a novel filter medium. The effect of inlet load of benzene-toluene mixtures on the biodegradation performance of the biofilter was studied. The maximum elimination capacities of 162.08 g/m3h for benzene and 110.09 g/m3h for toluene were obtained at a total inlet loading of 611.62 g/m3h.Inhibition of toluene degradation by the presence of benzene was observed in this study. The relationship between elimination capacity and inlet loading rate was studied. The carbon dioxide gas production rate was recorded and related to elimination capacity. Temperature variations during the biofiltration experiments were monitored. Axial variation of pollutant concentration in the biofilter bed was studied and the lowest part of the biofilter column was found to remove approximately 40 % of the total removal which was due to enhanced biomass density. Keywords- Biofiltration, Removal Effeciency, Elimination Capacity, Volatile Organics.