Removal of polycyclic aromatic hydrocarbons from soil using surfactant and the white rot fungusPhanerochaete chrysosporium

Abstract

The bioremediation of soil contaminated with polycyclic aromatic hydrocarbons (PAH) is often limited by a low bioavailability of the contaminants. Non-ionic surfactants, such as Tween 80, when above their critical micelle concentration (CMC), can ef®ciently enhance the bioavailability of PAHs in contaminated soil by increasing solubility and dissolution rates. However, disposing of this micelle-contaminated spent washwater can be a major problem. The aim of this study was to combine surfactant soil washing techniques using Tween 80 with the versatile lignin-degrading system of the white rot fungus, Phanerochaete chrysosporium, to bioremediate PAH-contaminated soil. Approximately 85% (w/w) of a total of nine PAHs in an aged (1 month) contaminated soil (total PAH concentration = 403.61 mg g À1 ) could be solubilized in a 2.5% (w/v) Tween 80 solution at a soil/water ratio of 1:10. The washwater was then catabolized by a 3-day-old culture of P chrysosporium under a stationary condition. The disappearance of most PAHs tested (molecular weight ! 178) correlated well with their ionization potentials and 66.4% (w/w) of the total PAHs in washwater with 2.5% (w/v) Tween 80 was catabolized after 11 days of culture. The catabolism was enhanced to 86% (w/w) using a lower concentration of 0.5% (w/v) Tween 80. The initial oxidation rate of total PAHs based on the ®rst 4 days of culture remained almost constant at approximately 1.88 mg cm À3 day À1 when the Tween 80 concentration in washwater was increased from 0.5% to 2.5% (w/v). The combination of soil washing and white rot fungus catabolization of PAH using 2.5% (w/v) Tween 80 eliminated the total PAH concentration in the contaminated soil by 56.4% (w/w) after 11 days. The results suggest that PAHcontaminated soil may be cleansed by using a combination of surfactant soil washing and white rot fungus catabolism.

Polysorbate 80 UV/vis spectral and chromatographic characteristics – defining boundary conditions for use of the surfactant in dissolution analysis

“…Polysorbate 80, a polymeric non-ionic surfactant, is commonly used for applications in the chemical, cosmetic, food, environmental, and pharmaceutical industries [1][2][3][4][5][6][7][8][9][10][11][12][13]. These uses typically involve the ability of the surfactant to stabilize emulsions or to increase the aqueous solubility of hydrophobic compounds.…”

Promising abilities of mercapto‐degrading Staphylococcus capitis strain SH6 in both crude oil and waste motor oil as sole carbon and energy sources: its biosurfactant production and preliminary characterization

“…Soil contaminations with hydrocarbons are widely proven to be persistent in nature, poorly soluble in water, and often associated with toxic and carcinogenic effects . Current soil remediation techniques require basically heavy, expensive equipments, and even display several environmental risks . The low water solubility of hydrocarbons constitutes one of the main problems affecting their biodegradation efficiency .…”

Modeling Surfactant LAS Influenced PAHs Migration in Soil Column

“…Early studies have demonstrated that PAHs sorption to soil was chemical non-equilibrium sorption (Danzer and Grathwohl, 1998;Dianne et al, 2002;Zheng and Obbard, 2000).…”

“…Surfactant soil flushing is an important chemical remediation technique in the clean-up of contaminated soil (Kim and Osako, 2003;Dianne and Parmely, 2002;Zheng and Obbard, 2000). Compared with the conventional pump-and-treat technique, the remediation efficiency could be increased significantly.…”