In this study, GC-MS methods were developed for identifying and quantifying nineteenand five pre-selected PCB congeners in solution. The developed methods wererepeatable (≤ 4.9 %) and reproducible (≤ 7.7 %) with detection limits of1.25 - 15 ng µL-1. The extraction of PCBs from soil and water samples was achievedusing the ASE and C18 (EC) SPE methods with recoveries of 81 - 94 % and 41 - 49 %respectively. Although none of the target PCB congeners were detected in soil and watersamples collected from Lagos, Nigeria, similar recoveries were obtained from spikedsamples; indicating that the developed methods could be satisfactorily used to extractPCBs from environmental samples.The adsorption of PCBs from aqueous solutions onto activated carbons - PAC, GAC andEAC was examined using batch experiments. The removal efficiencies obtained forPAC (75 - 90 %), GAC (79 - 99 %) and EAC (60 - 74 %) indicated that each AC couldbe successfully used to remove PCBs from water. In contrast to EAC, which had a slightdecrease in performance as the concentration of aqueous solution increased, a significantdecrease in performance was observed for PAC and GAC. The equilibrium dataobtained for each AC was well described by the Langmuir isotherm modelcorresponding to the presence of a homogeneous surface. Amongst the three ACs, EAChad the highest maximum adsorption capacity (35 mg g-1) compared to PAC(29.4 mg g-1) and GAC (30.4 mg g-1). The adsorption kinetic data obtained for each AChad a better fit to the pseudo second-order kinetic model indicating that chemisorptionwas responsible for the sorption of PCBs onto each AC. The optimum performance ofthe three ACs was achieved at solution pH 3.
| Date of Award | 14 Oct 2016 |
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| Original language | English |
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| Awarding Institution | - University Of Strathclyde
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