Use of Surfactants in Soil and Groundwater Remediation

Abstract

Due to potential risks of hazardous materials to human beings and to environment, numerous research has been initiated to investigate their removal, control, transportation and monitoring. The major organic pollutants in the subsurface environment are pesticides, PCBs, PAHs, organic liquids (LNAPLs, DNAPLs), and organic sludges/solids. The removals of these compounds are difficult due to poor solubilities of these compounds in aqueous phase. In addition, the rate limited solubilization makes the problem even more complicated. Since the traditional remediation methods were unsuccessful in cleaning up most contaminated fields, new novel methods have been investigated. Surfactants have been used in soil remediation processes to improve removal of pollutants from soil and groundwater due to their unique properties like micelle formation. Surfactants are a class of natural and synthetic chemicals that promote the wetting, solubilization, and emulsification of various types of organic and inorganic contaminants. They are utilised within chemical physical technologies like in situ soil flushing and ex situ soil washing for remediation of unsaturated zone and pump and treat for aquifer remediation. There are many other investigations on surfactant enhanced remediation technologies including bioremediation and electro kinetic remediation. In this study, the use of surfactants in remediation technologies is discussed. Their advantages and disadvantages for wider applications are outlined.