[Removal mechanism of light non-aqueous phase liquid from soil and groundwater by surfactant].
Surfactant increases solubilization of n-hexadecane and reduces interfacial tension between surfactant and n-hexadecane, which are very important for the removal of residual LNAPLs in porous media. After the solubilization of n-hexadecane and interfacial tension between Triton X-100 solution and n-hexadecane were studied through experiments, the forming rule of different states of n-hexadecane were analyzed through equilibrium washing experiment and sand pillar leaching experiment. The experimental results show that: the dissolving ability was proportional to the concentration of Triton X-100 solution, and MSR = 1.680 4 and lgk(mc) = 1.715 8 calculated by solubilization of n-hexadecane when Triton X-100 solution concentration was large than CMC. The interfacial tension was inversely proportional to Triton X-100 solution concentration, and the variation was in accord with Gauss model (R2 = 0.996 4). Dissolved state and free state n-hexadecane had very good corresponding relation with solubilization and reducing interfacial tension respectively. Both solubilization and reducing interfacial tension could remove n-hexadecane from porous media. Reducing interfacial tension increased the flow ability of n-hexadecane effectively, and it removed most of residual n-hexadecane in soil and groundwater remediation.
State Key Joint Laboratory of Environmental Simulation and Pollution Control, School of Environment, Beijing Normal University, Beijing 100875, China. yangjian@mail.bnu.edu.cn
Jian
J
Yang
Jia-Jun
JJ
Chen
Yi
Y
Lu
D052918:Environmental Restoration and Remediation / Q000379:methods*; D012989:Soil Pollutants / Q000737:chemistry / Q000302:isolation & purification*; D013501:Surface-Active Agents / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*
D012989:Soil Pollutants; D013501:Surface-Active Agents; D014874:Water Pollutants, Chemical