Achievement

Surdo, E. M. et al, Sorptive and reactive scavenger-containing sandwich membranes as contaminant barriers: The barrier properties of composite membranes containing either zero-valent iron nanoparticles or powdered activated carbon mixed into an aqueous clay suspension and sandwiched between two sheets of high-density polyethylene were measured using carbon tetrachloride and trichloroethylene as model contaminants. The lag time to trichloroethylene breakthrough increased 17-fold when 24 wt% powdered activated carbon was mixed into the 400-m-thick center layer of the composite. Zero-valent iron was successful in extending the lag time for carbon tetrachloride but not for trichloroethylene, presumably because the latter reaction with zero-valent iron is slow relative to diffusion.