Combining fluorine-specific graphite furnace-molecular absorption spectrometry with mineralization approaches

Abstract

An aqueous operation mode for graphite furnace molecular absorption spectrometry (GF-MAS) was established for the determination of total fluorine by combination with mineralization techniques. Pyrohydrolytic combustion was identified as the most effective sample preparation method, offering quantitative fluorine recovery after conversion into fluoride with a sample dilution factor of down to 100. Benchmarked against direct GF-MAS analysis, species discrimination, which can bias the results for up to two orders of magnitude, was eliminated. The procedure was evaluated using consumer product extracts spiked with different perfluorinated compounds. Detection limits of 40 μg per kg fluorine were obtained for the combined approach, offering a promising addition to combustion ion chromatography both in terms of sensitivity and sample throughput.