Remediation of petroleum-contaminated soil after composting by sequential treatment with Fenton-like oxidation and biodegradation

• Published in: Bioresource technology 2010-04, Vol.101 (7), p.2106-2113
• Main Authors: Lu, Mang, Zhang, Zhongzhi, Qiao, Wei, Wei, Xiaofang, Guan, Yueming, Ma, Qingxia, Guan, Yingchun
• Format: Article
• Language: English
• Subjects: Bacteria - isolation & purification; Biodegradation, Environmental; Biological and medical sciences; Biological treatment of sewage sludges and wastes; Bioremediation; Bioslurry; Biotechnology; Colony Count, Microbial; Environment and pollution; Fourier transform ion cyclotron resonance mass spectrometry; Fundamental and applied biological sciences. Psychology; Hydrogen Peroxide - analysis; Hydrogen Peroxide - metabolism; Hydrogen-Ion Concentration; Industrial applications and implications. Economical aspects; Iron - analysis; Iron - metabolism; Methylene Chloride - chemistry; Oxidation-Reduction; Oxygen; Petroleum - metabolism; Soil; Soil Microbiology; Soil Pollutants - isolation & purification; Spectrometry, Mass, Electrospray Ionization; The van Krevelen diagram
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2009.11.002

A laboratory study was conducted to enhance removal of residual contaminants after composting in a highly petroleum-contaminated soil by combining Fenton-like pretreatment with biodegradation. The contaminants were characterized by Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) during soil treatment. The optimum molar ratio of H 2O 2 and Fe 3+ was 300/1 determined in batch experiments. At the end of Fenton-like treatment, total dichloromethane-extractable organics (TEO) decreased from 32,400 to 21,800 mg kg −1 soil, and the toxicity of soil was reduced greatly in the preoxidation process. A significant loss of the number of soil microorganisms was observed in the Fenton-like reaction. During the microbial treatment period, 50.6% of TEO was destroyed. Numerous varieties of polar compounds containing nitrogen and oxygen were identified by FT-ICR MS. The number of compounds containing two oxygen atoms dropped from 604 to 163 during Fenton-like oxidation, and increased again to 577 after biodegradation.