Efficiency of Dioxin Recovery from Fly Ash Samples during Extraction and Cleanup Process

摘要

The data from preliminary investigations of the efficiency of dioxin recovery from fly ash samples during sample extraction and subsequent column cleanup of sample extracts are discussed. Steps of the extraction and the column cleanup procedures were evaluated by using radiolabeled (14)C-dioxins as tracers. Sample extracts and eluate fractions were analyzed by liquid scintillation counting and the results confirmed by gas chromatography/mass spectrometry. Recovery data of spiked 2,3,7,8-tetrachlorodibenzo-p-dioxin-(14)C (TCDD-(14)C) and octachlorodibenzo-p-dioxin-(14)C (OCDD-(14)C) in carbon-free fly ash and fly ash containing from 0.1 to 10% carbon are discussed. The data indicate that the amount of carbon in the fly ash may affect the recovery of dioxins. The data from the study will be used to determine procedural areas that need improvements or modifications to allow the accurate determination of trace levels of dioxins and furans in fly ash. Various extraction techniques of fly ash and cleanup of sample extracts by column chromatography were evaluated. Several chromatographic media and eluting solvents were investigated. Information from this study will support efforts to monitor the hazardous composition, if any, of fly ash from various types of incinerators that use different types of combustible materials, mainly municipal wastes.