The amount released will depend on the material being burnt or smelted e.g. “dirty” brown coal releases more F. into the air than the hard “clean” coal anthracite. – Fluorides are released into the environment viacoal combustion and process waters and waste from various industrial processes, including steel manufacture, primary aluminium, copper and nickel production, phosphate ore processing, phosphate fertilizer production and use, glass, brick and ceramic manufacturing, and glue and adhesive production, oil refining, car exhausts and welding.
The use of the fluoride-containing pesticide, sulfuryl fluoride as a food fumigant (trade name ProFume ®) as well as the fluoridation of drinking water, also contribute to the release of fluoride from anthropogenic sources. Based on available data, phosphate ore production and use, as well as aluminium manufacture are the major industrial sources of fluoride release into the environment.
Sulfuryl fluoride (SO2F2) is a radiatively active industrial chemical released into the atmosphere in significant (ktonne/year) quantities. The potential for SO2F2 to contribute to radiative forcing of climate change needs to beassessed. Long path length FTIR/smog chamber techniques were used to investigate the kinetics of the gas-phase reactions of Cl atoms, OH radicals, and O3 with SO2F2, in 700 Torr total pressure of air or N2 at 296 ± 1 K. Upper limits of k(Cl + SO2F2) < 9 × 10−19, k(OH + SO2F2) < 1.7 × 10−14 and k(O3 + SO2F2) < 5.5 × 10−24 cm3 molecule−1 s−1 were determined. Reaction with Cl atoms, OH radicals, or O3 does not provide an efficient removal mechanism for SO2F2. The infrared spectrum of SO2F2 is reported and a radiative efficiency of 0.196 W m−2 ppbv−1 was calculated. Historic production data estimates are presented which provide an upper limit for expected atmospheric concentrations. The radiative forcing of climate change associated with emissions of SO2F2 depends critically on the atmospheric lifetime of SO2F2.3 + SO2F2) < 5.5 × 10−24 cm3 molecule−1 s−1 were determined. Reaction with Cl atoms, OH radicals, or O3 does not provide an efficient removal mechanism for SO2F2. The infrared spectrum of SO2F2 is reported and a radiative efficiency of 0.196 W m−2 ppbv−1 was calculated. Historic production data estimates are presented which provide an upper limit for expected atmospheric concentrations.
The radiative forcing of climate change associated with emissions of SO2F2 depends critically on the atmospheric lifetime of SO2F2.
Further research is urgently needed to define the magnitude of potential non-atmospheric sinks.
