Nanoscale and microscale iron emulsions for treating DNAPL
PHENOL; Chemistry, Multidisciplinary; Engineering, Environmental
This study demonstrated the feasibility of using emulsified nanoscale and microscale iron particles to enhance dehalogenation of DNAPL free-phase. The emulsified system consisted of a surfactant-stabilized, biodegradable oil-in-water emulsion with nanoscale or microscale iron particles contained within the emulsion droplets. It was demonstrated that DNAPLs, such as TCE, diffuse through the oil/surfactant membrane of the emulsion particle whereupon they reach an aqueous interior and the surface of an iron particle where dehalogenation takes place. The hydrocarbon reaction byproducts of the dehalogenation reaction, primarily ethene (no chlorinated products detected), diffuse out of the emulsion droplet. This study also demonstrated that an iron-emulsion system could be delivered in-situ to the DNAPL pool in a soil matrix by using a simulated push well technique. Iron emulsions degraded pure TCE at a rate comparable to the degradation of dissolved phase TCE by iron particles, while pure iron had a very low degradation rate for free-phase TCE. The iron-emulsion systems can be injected into a sand matrix where they become immobilized and are not moved by flowing water. It has been documented that surfactant micelles possess the ability to pull pooled TCE into emulsion droplets where degradation of TCE takes place.
Chlorinated Solvent and Dnapl Remediation: Innovative Strategies for Subsurface Cleanup
"Nanoscale and microscale iron emulsions for treating DNAPL" (2003). Faculty Bibliography 2000s. 3776.