Copper-ion assisted photochemical vapor generation of bromide and bromate

Abstract

Significant enhancements in the photochemical vapor generation (PVG) efficiencies of both Br- and BrO3- species from a 2 % acetic acid medium occur in the presence of 10 mg L-1...

Atomic spectrometry update: review of advances in atomic spectrometry and related techniques

“…LODs of 0.03 and 3 μg L −1 for Br − and Cl − respectively were achieved using ICP-MS detection. Very similar conclusions were drawn by de Oliveira et al 37 using 2% acetic acid and 10 mg L −1 Cu 2+ to generate CH 3 Br from Br − and BrO 3 − , using both 19 W (185 nm) and 15 W (254 nm) UV lamps. Volatile Br species were generated from both Br − and BrO 3 − at 185 nm but only from Br − at 254 nm, making Br speciation possible if both lamps were used in parallel.…”

“…LODs of 0.03 and 3 mg L À1 for Br À and Cl À respectively were achieved using ICP-MS detection. Very similar conclusions were drawn by de Oliveira et al 37 and Brc free radical atom transfer from a copper bromide complex accounting for the high PVG efficiency. This research highlights the fact that the efficiency of PVG is affected by the addition of transition metal ions and organic compounds which was highlighted in three further studies.…”

Photochemical Vapor Generation of Halides in Organic-Acid-Free Media: Mechanism Study and Analysis of Water Samples

“…Very recently, Sturgeon et al have reported the same efficacy of Cu 2+ for fluoride, although with a much lower yield (<1%). In a preliminary study of this work and the very recent paper by Sturgeon’s group, Cu 2+ was found to have a positive impact on the PCVG of bromide. More surprisingly, an obvious PCVG-ICPMS signal was observed even without acetic acid (note that Cu 2+ was added as an acetate); in other words, the photochemical reaction may occur in organic-acid-free media.…”

“…In this way, alkyl iodides can be efficiently formed from the UV-illuminated organic acid media . With the assistance of Cu 2+ ions, the PCVG of chloride, fluoride, and lately bromide and bromate can also be attained, yielding methyl halides as main gaseous products. The charge transfer to solvent (CTTS), ligand to metal charge transfer (LMCT), and halogen atom transfer (HAT) models have been proposed to elucidate the possible reaction pathway but have not yet been illustrated experimentally.…”

Ultrasensitive Detection of Ruthenium by Coupling Cobalt and Cadmium Ion-Assisted Photochemical Vapor Generation to Inductively Coupled Plasma Mass Spectrometry

“…Among various VG techniques, photochemical VG (PVG) remains relatively immature , but rapidly developing and expanding regarding the number of analytes for which it can be applied. This has included metalloids and elements typically forming volatile hydrides and Hg, − the halogens, − and transition metals. ,,,− The analyte is converted into a volatile species during UV irradiation of an aqueous reaction medium typically containing low molar mass carboxylic acids such as formic and acetic acid. ,,, Reducing radical species (H • , R • , and CO 2 •– ), as well as aquated electrons (e (aq) – ), are generated through the action of UV photons that subsequently interact with the analyte to form volatile species, including hydrides, carbonyls, or alkylated compounds, depending on the analyte and reaction medium used . The exception is Os, for which both photo-oxidation from water or in the presence of HNO 3 has been described yielding (presumably) volatile OsO 4 , and, most recently, photoreduction from an acetic acid medium …”