title: Remediation of PAH-contaminated soil at a gas manufacturing plant by a combined two-phase partition system washing and microbial degradation process.
abstract: The aim of this study was to design a remediation technique using both soil washing and microbial degradation to remove polycyclic aromatic hydrocarbons (PAHs) from contaminated soil. PAH biodegradation by inoculation of Mycobacterium sp. was first tested. The effectiveness of washing agents (Tween 80 solution, biodiesel, and a two-phase partition system (TPPS)) was then evaluated with column experiments. Third, the combination of TPPS washing and microbial degradation was studied. PAH bioavailability before and after biodegradation and the joint remediation was also assessed using hydroxypropyl-β-cyclodextrin (HPCD) extraction. Only phenanthrene and anthracene were noticeably biodegradable when the soil was inoculated with Mycobacterium sp. TPPS containing 2% (v/v) biodiesel and 2.5% (w/v) Tween 80 was used as the washing agent for the joint remediation test because it gave higher PAH extractions than Tween 80 solution with lower doses, and there was less residue in the soil. Joint TPPS washing and microbial degradation gave a total PAH removal of 92.6%, which was much higher than the results from either the biodegradation or washing experiments alone. Removals of all high molecular weight (HMW) PAHs were improved. Bioavailable concentrations of all PAHs decreased significantly after the joint remediation process, indicating that there were reduced risks from all PAHs. The results demonstrate that the combination of TPPS washing and microbial degradation is a useful and innovative process for remediation of PAH-contaminated soils.
authors: Environmental Engineering Institute, College of Resources and Civil Engineering, Northeastern University, NO. 3-11, Wenhua Road, Shenyang, 110819, People's Republic of China.
authors: Xuan
authors: X
authors: Gong
authors: Xinyang
authors: X
authors: Xu
authors: Zongqiang
authors: Z
authors: Gong
authors: Xiaojun
authors: X
authors: Li
authors: Chunyun
authors: C
authors: Jia
authors: Meixia
authors: M
authors: Guo
authors: Haibo
authors: H
authors: Li
mesh_terms: D000073738:2-Hydroxypropyl-beta-cyclodextrin; D001673:Biodegradation, Environmental; D056804:Biofuels; D009161:Mycobacterium / Q000254:growth & development; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D011136:Polysorbates / Q000737:chemistry; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000032:analysis*; D047392:beta-Cyclodextrins / Q000737:chemistry
chemical_list: D056804:Biofuels; D011084:Polycyclic Aromatic Hydrocarbons; D011136:Polysorbates; D012989:Soil Pollutants; D047392:beta-Cyclodextrins; D000073738:2-Hydroxypropyl-beta-cyclodextrin