Quantitative energy-dispersive spectrometry X-ray analyses (±10%) were performed on approximately 300 Pb halide particles (0.2-2 μm in diameter) from the Phoenix aerosol. The most abundant species appears to be α-2PbBrCl-NH4Cl, comprising about one-third of the total particles. Other compounds identified are PbBrCl, (PbO)2-PbBrCl, and probably 3Pb3(PO4)2.PbBrCl. Particles having compositions different from previously reported atmospheric Pb haiide compounds might represent mixed phases or as yet unidentified species. Only about 5% of the particles have Br/C1 molar ratios > 1.0, and no particles with only Br and Pb were observed. It is suggested that Br loss occurs from atmospheric Pb halides having Br/C1 or Br/Pb > 1.0, while Pb halides with Br/CI < ~1.0 experience little haiide loss.
ASJC Scopus subject areas
- Environmental Chemistry