Effect of amendment of ο-xylene degrading bacteria on performance of biological gas treatment for BTEX contaminated air

Abstract

This study described the effect of amendment of o-xylene degrading bacteria on performance of biological gas treatment for BTEX (Benzene, Toluene, Ethylbenzene, Xylene) -contaminated air using bubble column, which allowed passage of contaminated air through a microbial culture. Continuous treatment of o-xylene-contaminated air was carried out using soil suspension as a microbial inoculum. Incubation period lasted five to fourteen days to remove >90% ofo-xylene using the bubble column. A longer period was needed when higher concentrations ofo-xylene were present in the BTEX-contaminated air. On the other hand, 97% of o-xylene was removed after only 2 days incubation wheno-xylene-degrading bacteria, Rhodococcus opacusTKN14, and soil suspension were used as the inoculum. Furthermore, when similar strain of bacteria and soil suspension were used as the inoculum to decontaminate the air, including BTEX, which vaporized from actual contaminated soil, >90% of benzene, toluene, ethylbenzene and o-, m-, p-xylene were removed by bubble column after 6 days incubation. From these results, we concluded that a useful microbial community for biological treatment of BTEX contaminated air could be rapidly constructed using soil suspension ando-xylene degrading bacteria as inoculum.