Biological removal of polychlorinated dibenzo-p-dioxins from incinerator fly ash by Sphingomonas wittichii RW1.
The ability of Sphingomonas wittichii strain RW1 to remove polychlorinated dibenzo-p-dioxins (PCDDs) from fly ash was investigated. All experiments were carried out in a slurry-phase system. Preliminary studies with resting cells of strain RW1 in a model fly ash system showed the complete removal of dibenzofuran (DF) and 81% of dibenzo-p-dioxin (DD). Incubation of real fly ash collected from municipal waste incinerators with strain RW1 for 15 days resulted in a 75.5% reduction in toxic PCDDs. When the same experiment was carried out using dead strain RW1 cells a 20.2% reduction in toxic PCDDs was observed, indicating that adsorption onto biomass was an important factor in dioxin elimination. Further analyses revealed that live strain RW1 cells removed 83.8% of the 2,3,7,8-substituted congeners from the fly ash, while dead cells removed 32.1% of the same congeners. To enhance the removal efficiency of toxic PCDDs, the effects of adding surfactant, repeated inoculation, and pre-adaptation of cultures were also studied. The removal of toxic PCDDs was enhanced by up to 10.3% upon repeated inoculation of the strain RW1, but was not much affected by the addition of surfactant. The present results suggest that S. wittichii strain RW1 is a potential candidate for the industrial removal of PCDDs from incinerator fly ash.
Nam
In-Hyun
IH
School of Environmental Science and Engineering, Pohang University of Science and Technology, Pohang 790-784, Korea.
Hong
Hyo-Bong
HB
Kim
Young-Mo
YM
Kim
Byung-Hoon
BH
Murugesan
Kumarasamy
K
Chang
Yoon-Seok
YS
D000391:Air Microbiology; D000393:Air Pollutants / Q000302:isolation & purification*; D001673:Biodegradation, Environmental; D002244:Carbon / Q000737:chemistry*; D060729:Coal Ash; D017745:Incineration; D052638:Particulate Matter; D000072317:Polychlorinated Dibenzodioxins / Q000031:analogs & derivatives* / Q000302:isolation & purification / Q000378:metabolism; D020578:Sphingomonas / Q000378:metabolism*; D013997:Time Factors
D000393:Air Pollutants; D060729:Coal Ash; D052638:Particulate Matter; D000072317:Polychlorinated Dibenzodioxins; D002244:Carbon