| Abstract
| - A poly(vinyl alcohol) (PVA) membrane containing iron(Fe0) particles was developed and tested as a model barrierfor contaminant containment. Carbon tetrachloride,copper (Cu2+), nitrobenzene, 4-nitroacetophenone, andchromate (CrO42-) were selected as model contaminants.Compared with a pure PVA membrane, the Fe0/PVAmembrane can increase the breakthrough lag time forCu2+ and carbon tetrachloride by more than 100-fold. Theincrease in the lag time was smaller for nitrobenzeneand 4-nitroacetophenone, which stoichiometrically requiremore iron and for which the PVA membrane has ahigher permeability. The effect of Fe0 was even smallerfor CrO42- because of its slow reaction. Forty-five percentof the iron, based on the content in the dry membraneprior to hydration, was consumed by reaction with Cu2+and 15% by reaction with carbon tetrachloride. Similarly,25%, 17%, and 6% of the iron was consumed by nitrobenzene,4-nitroacetophenone, and CrO42-, respectively. Thesepercentages approximately double when the loss of ironduring membrane hydration is considered. The permeabilityof the Fe0/PVA membrane after breakthrough was withina factor of 3 for that of pure PVA, consistent with theory.These results suggest that polymer membranes withembedded Fe0 have potential as practical contaminantbarriers.
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