Assessment of zero-valent iron as a permeable reactive barrier for long-term removal of arsenic compounds from synthetic water.
Zero-valent iron (ZVI) has great potential to be used as a remediation material for the removal of a wide range of pollutants from groundwater. The present study assessed the potential of ZVI for arsenic remediation by investigating (i) the removal kinetics of arsenic by ZVI in a batch reactor and (ii) the longevity of ZVI to remove arsenic in a flow-through column system which mimics the permeable reactive barrier (PRB) technology. Results of the batch experiments showed an effective removal (99.5%) of arsenic compounds from the synthetic water samples. Based on our kinetic study, the arsenic removals are expected to occur in a timescale of less than a few hours in typical PRB treatment conditions using ZVI (e.g. [ZVI] > 20 g/L and [As] < 1 mg/L). The flow-through columns were continuously operated for 360 days at a flow rate of 2 mL/h. Samples were taken at regular intervals (90, 150, 230 and 360 days) and analysed for total arsenic concentration. The removal rates decreased by (45% in aerobic and 39% in anoxic) after 360 days of operation indicate that the regular replacement of the reactive material would be required for efficient removal of arsenic.
Lee
Kui-Jae
KJ
Division of Biotechnology, College of Environmental and Bioresource Sciences, Chonbuk National University, Iksan 570-752, South Korea.
Lee
Yunho
Y
Yoon
Jeyong
J
Kamala-Kannan
Seralathan
S
Park
Seung-Moon
SM
Oh
Byung-Taek
BT
D000327:Adsorption; D001151:Arsenic / Q000737:chemistry* / Q000302:isolation & purification; D052918:Environmental Restoration and Remediation / Q000379:methods*; D007501:Iron / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D010084:Oxidation-Reduction; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry* / Q000302:isolation & purification; D018508:Water Purification / Q000379:methods*
D014874:Water Pollutants, Chemical; D014867:Water; D007501:Iron; D001151:Arsenic