A polymer membrane containing Fe(0) as a contaminant barrier.
A poly(vinyl alcohol) (PVA) membrane containing iron (Fe(0)) particles was developed and tested as a model barrier for contaminant containment. Carbon tetrachloride, copper (Cu2+), nitrobenzene, 4-nitroacetophenone, and chromate (Cr04(2-)) were selected as model contaminants. Compared with a pure PVA membrane, the Fe(0)/PVA membrane can increase the breakthrough lag time for Cu2+ and carbon tetrachloride by more than 100-fold. The increase in the lag time was smaller for nitrobenzene and 4-nitroacetophenone, which stoichiometrically require more iron and for which the PVA membrane has a higher permeability. The effect of Fe(0) was even smaller for CrO4(2-) because of its slow reaction. Forty-five percent of the iron, based on the content in the dry membrane prior 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 CrO4(2-), respectively. These percentages approximately double when the loss of iron during membrane hydration is considered. The permeability of the Fe(0)/PVA membrane after breakthrough was within a factor of 3 for that of pure PVA, consistent with theory. These results suggest that polymer membranes with embedded Fe(0) have potential as practical contaminant barriers.
Shimotori
Tsutomu
T
Department of Civil Engineering, University of Minnesota, 500 Pillsbury Drive Southeast, Minneapolis, Minnesota 55455, USA.
Nuxoll
Eric E
EE
Cussler
Edward L
EL
Arnold
William A
WA
D004785:Environmental Pollutants / Q000302:isolation & purification*; D005374:Filtration; D007501:Iron / Q000737:chemistry*; D007700:Kinetics; D008567:Membranes, Artificial; D011142:Polyvinyl Alcohol / Q000737:chemistry*
D004785:Environmental Pollutants; D008567:Membranes, Artificial; D011142:Polyvinyl Alcohol; D007501:Iron