Enhanced Desorption of PAHs from Manufactured Gas Plant Soils Using Different Types of Surfactants

Surfactant enhanced remediation is thought to be an effective method for the remediation of soils polluted with hydrophobic organic compounds. Desorption of polycyclic aromatic hydrocarbons(PAHs) from an abandoned manufactured gas plant(MGP) soil was evaluated using four eluting agents including Triton X-100(TX100),sodium dodecylbenzene sulfonate(SDBS),rhamnolipid water solution(RWS) and rhamnolipid fermentation broth(RFB). The weight solubilization ratios for acenaphthene and fluorene were in the order of TX100 > SDBS > RWS > RFB. The Sm value,which indicates the maximum amounts of surfactants adsorbed in the soil,was in the order of RWS > RFB > SDBS > TX100. By using 8 g L-1of TX100,SDBS and RWS and 100% of RFB,the T-PAHs removal for the MGP soil contaminated with 207.86 mg T-PAHs kg-1 dry soil was 48.0%,45.7%,1.9%,and 8.6%,respectively,while that decreased to 41.6%,37%,0.38%,and 1.3% for the soil contaminated with 3 494.78 mg T-PAHs kg-1 dry soil. Only 8 g L-1 TX100 could remove all types of the 16 PAHs partly in the MGP soil,and the removal efficiencies of different PAHs ranged from 13% to 77.8%. The results of this study herein provide valuable information for the selection of TX100 surfactant for remediating PAH-contaminated soils in MGP.