Remediation of petroleum-contaminated soil after composting by sequential treatment with Fenton-like oxidation and biodegradation.
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(2)O(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.
Lu
Mang
M
State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249, China.
Zhang
Zhongzhi
Z
Qiao
Wei
W
Wei
Xiaofang
X
Guan
Yueming
Y
Ma
Qingxia
Q
Guan
Yingchun
Y
D001419:Bacteria / Q000302:isolation & purification; D001673:Biodegradation, Environmental; D015169:Colony Count, Microbial; D006861:Hydrogen Peroxide / Q000032:analysis / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000032:analysis / Q000378:metabolism*; D008752:Methylene Chloride / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen; D010578:Petroleum / Q000378:metabolism*; D012987:Soil; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000302:isolation & purification*; D021241:Spectrometry, Mass, Electrospray Ionization
C045076:Fenton's reagent; D010578:Petroleum; D012987:Soil; D012989:Soil Pollutants; D008752:Methylene Chloride; D006861:Hydrogen Peroxide; D007501:Iron; D010100:Oxygen