Authors: GoUn Nam Riza Gabriela Bonifacio JungHwan Kwon Yongseok Hong
Publish Date: 2016/06/22
Volume: 23, Issue: 18, Pages: 18901-18910
Abstract
Passive sampling of volatile organic chemicals from soil and groundwater is primarily important in assessing the status of environmental contamination A group of low molecular weight pollutants usually found in petroleum fuels benzene toluene ethylbenzene and xylenes BTEX was studied for its kinetics and equilibrium partitioning with singlephase passive samplers using polydimethylsiloxane PDMS and polyoxymethylene POM as sorbing phase PDMS 1 mm and POM 0076 mm sheets were used for sorption of BTEX and concentrations were analyzed using GCFID The equilibrium absorption and desorption of PDMS in water was achieved after 120 min while POM sheets absorbed up to 35 days and desorbed in 7 days The kinetic rate constants in PDMS is higher than in POM up to 3 orders of magnitude Logarithms of partition coefficient were determined to be in the range of 16–28 for PDMS and 21–31 for POM The results indicate that POM is a stronger sorbent for BTEX and has slower equilibration time than PDMS The partitioning process for both polymers was found to be enthalpydriven by measurement of K d values at varying temperatures K d values increase at low temperature and high ionic strength conditions Presence of other gasoline components as well as dissolved organic matter did not significantly affect equilibrium partitioning A good 11 correlation between the measured and the predicted concentrations was established on testing the potential application of the constructed PDMS sampler on natural soils and artificial soils spiked with gasolinecontaminated water
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