In by admin

Name Dr. Amel Garbou
Organization or Institution University of Central Florida (UCF)
Presentation Type Poster
Topic Environmental
Title

Comparative Study for the Removal and Destruction of Pentachloroanisole versus Pentachlorophenol by Ball-milled Zero-Valent Magnesium/Graphite in an Acidified Ethanol

Author(s)

Garbou Amel, Clausen Christian and Yestrebsky Cherie

Author Institution(s)

University of Central Florida (UCF)

Abstract

Chlorophenols (CPs) are highly toxic compounds, usually found in soils, water, and effluents resulting from industrial activities. In the environment, CPs can be biologically transformed to Chloroanisoles (CAs), which are compounds that have similar properties to CPs. However, CAs have a higher tendency to bioaccumulate and resist degradation because of their lipophilicity. The most toxic congeners for CAs and CPs are the pentachloroanisole (PCA) and pentachlorophenol (PCP). Remediation of these compounds is highly sought after due to their toxicity in the environment. The aim of this work is to demonstrate the capabilities of using zero-valent magnesium powder ball-milled with graphite (ZVMg/C) in ethanol solvent and acetic acid to enhance the reductive dechlorination of both PCA and PCA. The results of the method, are compared for both target analytes. Both substrates were degraded to less-chlorinated byproducts within the first four hours; however PCP degraded at a faster rate with no detection at seven minutes. The more heavily-chlorinated byproducts showed faster degradation rates for both compounds, which also had 2,4-dichlorinated congeners in common as major byproducts. The mole balances of PCA and PCP were 92.6% and 94.8%, respectively. Further studies were done to enhance degradation kinetics by re-spiking with acetic acid after two weeks. Although complete dechlorination was still not achieved, a slight improvement was observed for both compounds, more so with respect to PCP. Kinetic data followed pseudo first-order trends for the degradation of both PCA and PCP. It is anticipated that an understanding of these fundamental chemical processes will allow this system to be tailored to a wide range of complex environmental media.