Combined effects of DOM extracted from site soil/compost and biosurfactant on the sorption and desorption of PAHs in a soil–water system

• Published in: Journal of hazardous materials Vol. 190; no. 1; pp. 883 - 890
• Main Authors: Yu, Hui, Huang, Guo-he, An, Chun-jiang, Wei, Jia
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 15.06.2011; Elsevier
• Subjects: Adsorption; Applied sciences; Biosurfactant; biosurfactants; chemical structure; Composting; composts; Decontamination. Miscellaneous; Desorption; DOM; Environmental Restoration and Remediation; Exact sciences and technology; food waste; Molecular structure; Partitioning; Petroleum; Phenanthrene; Phenanthrenes - isolation & purification; pollutants; Pollution; Polyallylamine hydrochloride; polycyclic aromatic hydrocarbons; Polycyclic Aromatic Hydrocarbons - isolation & purification; Pyrenes - isolation & purification; remediation; Soil; Soil (material); Soil - chemistry; Soil and sediments pollution; soil water; Sorption; Surface-Active Agents - chemistry; Water; Biosurfactant; Sorption; Soil; Desorption; DOM; Compost; Phenanthrene; Hydrocarbon; Molecular structure; Pollutant behavior; Mobility; Extract; Polycyclic aromatic compound; Soil pollution; Interstitial water; Petroleum; Persistent organic pollutant; Food waste; Transport process; Pyrene; Additive; Decontamination; Phase partition; Combined system; Organic compounds
• ISSN: 0304-3894; 1873-3336
• DOI: 10.1016/j.jhazmat.2011.04.026

► The combined DOM and biosurfactant significantly enhanced desorption of PAHs. ► Compost DOM exhibited higher desorption enhancement capacity than the soil DOM. ► Competition among PAHs, DOM and biosurfactant for sorption site determined desorption of PAHs from soil. ► Formation of DOM–biosurfactant complex enhance desorption extent of PAHs. The combined effects of DOM and biosurfactant on the sorption/desorption behavior of phenanthrene (PHE) and pyrene (PYR) in soil water systems were systematically investigated. Two origins of DOMs (extracted from soil and extracted from food waste compost) and an anionic biosurfactant (rhamnolipid) were introduced. The presence of DOM in the aqueous phase could decrease the sorption of PAHs, thus influence their mobility. Desorption enhancement for both PHE and PYR in the system with compost DOM was greater than that in the soil DOM system. This is due to the differences in specific molecular structures and functional groups of two DOMs. With the co-existence of biosurfactant and DOM, partitioning is the predominant process and the desorption extent was much higher than the system with DOM or biosurfactant individually. For PHE, the desorption enhancement of combined DOM and biosurfactant was larger than the sum of DOM or biosurfactant; however desorption enhancement for PYR in the combined system was less than the additive enhancement in two individual system under low PAH concentration. This could be explained as the competition sorption among PAHs, DOM and biosurfactant. The results of this study will help to clarify the transport of petroleum pollutants in the remediation of HOCs-contaminated soils.