Remediation of Diesel Contaminated Soil by Tween-20 Foam Stabilized by Silica Nanoparticles

Abstract

Diesel oil spills into soil from petroleum storage areas, pipelines are a major environmental hazard. There is thus an increasing demand for new, efficient agents for remediation of diesel contaminated soil. The aim of this study therefore was to analyze the efficiency of application of nanoparticle stabilized nonionic surfactant foams for remediation of diesel contaminated soil. Stable foams were produced from dispersions of hydrophilic, hydrophobic silica nanoparticles with nonionic surfactant Tween-20. The foam generated was then transferred to a column containing the contaminated soil. The maximum diesel oil removal efficiency obtained by applying Tween-20 foam stabilized with 0.5 wt% hydrophobic silica nanoparticle was 78%- much higher than that obtained for Tween-20 foam stabilized with 0.5 wt% hydrophilic silica nanoparticles. The Tween-20 surfactant solution alone showed only 42% maximum oil removal efficiency.