Efficient Dechlorination of Carbon Tetrachloride by Hydrophobic Green Rust Intercalated with Dodecanoate Anions

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• 作者：Karina B. Ayala-Luis ; Nicola G. A. Cooper ; Christian Bender Koch ; Hans Christian B. Hansen
• 刊名：Environmental Science & Technology (ES&T)
• 出版年：2012
• 出版时间：March 20, 2012
• 年：2012
• 卷：46
• 期：6
• 页码：3390-3397
• 全文大小：319K
• 年卷期：v.46,no.6(March 20, 2012)
• ISSN：1520-5851

文摘

The reductive dechlorination of carbon tetrachloride (CT) by Fe^II鈥揊e^III hydroxide (green rust) intercalated with dodecanoate, Fe^II₄Fe^III₂(OH)₁₂(C₁₂H₂₃O₂)₂路yH₂O (designated GR_C12), at pH 8 and at room temperature was investigated. CT at concentration levels similar to those found in heavily contaminated groundwater close to polluted industrial sites (14鈥?88 渭M) was reduced mainly to the fully dechlorinated products carbon monoxide (CO, yields >54%) and formic acid (HCOOH, yields >6%). Minor formation of chloroform (CF), the only chlorinated degradation product, was also detected (yields <6.3%). Reactions carried out with excess GR followed pseudo first-order kinetics with respect to CT with rate constants ranging from 6.5 脳 10^鈥? to 0.47 h^鈥?. These rate constants are comparable to those measured for CT dechlorinations mediated by zerovalent iron. Reduction of the highest concentration of CT (1.4 mM) proceeds until 56% of the Fe^II sites of GR_C12 was consumed. This reaction ceased after 10 h due to surface passivation of GR_C12.