Increasing the solubility enhancement of anionic DOWFAX surfactants

Previous research has demonstrated the robust nature of DOWFAX surfactants for enhanced subsurface remediation. However, these surfactants are not as effective as others in enhancing contaminant solubility. A series of experiments evaluated various methods of increasing the solubitity enhancement of the DOWFAX components (i.e., using a cosurfactant, adding an electrolyte, and forming middle-phase microemulsions). Results demonstrate that while increasing the alkyl chain produced slight increases in contaminant solubility, middle-phase microemulsions produced the greatest enhancements. Middle-phase microcmulsions were produced using an electrolyte, isobutanol, a cosurfactant, and one of the DOWFAX components. Middle-phase microemulsions increased contaminant solubilities by one to two orders of magnitude over DOWFAX surfactants alone, and by three to four orders of magnitude relative to water. Thus, DOWFAX-based microemulsion systems have the potential to significantly enhance contaminant solubility and expedite environmental remediation.