Characterization and Application of Surfactant Foams Produced from Ethanol-Sodium Lauryl Sulfate-Silica Nanoparticle Mixture for Soil Remediation

Abstract

Soils contaminated with diesel oil spilling from industrial areas, pipelines constitute a major environmental problem. This subsequently leads to the contamination of groundwater as well. Hence recently there is an increasing trend of usage of better techniques and agents that can perform diesel oil contaminated soil remediation with greater efficiency. The aim of this study is to report the potential, efficiency of using silica nanoparticle stabilized anionic surfactant foams for diesel contaminated soil remediation and also the different characteristics of the foam produced. Also comparison in terms of soil remediation efficiency using surfactant dispersions only were performed. The foams were produced from dispersions comprising of ethanol, anionic surfactant sodium lauryl sulfate (SLS) and silica nanoparticles, both hydrophobic and hydrophilic. The foamability and stability of the different foams were determined using the Dynamic Foam Analyzer DFA 100 (Kruss GmbH, Germany). The surfactant foams generated were then applied to the contaminated soil using a fabricated column. The results showed the gradual stabilization of the SLS foams by the use of the silica nanoparticles. The maximum diesel oil removal efficiency obtained by applying foam stabilized with 0.3 wt% hydrophobic silica nanoparticle, 10 vol% ethanol, 0.1 vol% SLS was 94.5%. The 0.3 wt% hydrophobic silica nanoparticle, 10 vol% ethanol, 0.1 vol% SLS surfactant solution showed only 61.5% maximum oil removal efficiency.