Analysis of water-soluble fraction of metals in atmospheric aerosols using aerosol counterflow two-jets unit and chemiluminescent detection

摘要

A new analytical system for a semi-continuous analysis of water-soluble fraction of particulate metals is described. The system combines the continuous sampling of atmospheric aerosols into deionized water using the Aerosol Counterflow Two-Jets Unit and on-line chemiluminescent detection of water soluble fraction of metals in collected aerosols. The potential of analytical system was studied using Fe~(3+), Cu~(2+) and Co~(2+) as model metals in atmospheric aerosols. The detection limits of particulate Fe~(3+), Cu~(2+) and Co~(2+) (S/N = 3) are 24, 41 and 0.4ngm~(-3), respectively. The presented set-up allows the determination of concentration of water-soluble fraction of particulate metals in 'real time' with time resolution of 30min. The system is sufficiently robust for the field application. The method has been applied to the measurement of selected metals in urban TSP (Total Suspended Particles) aerosols in Brno in the Czech Republic. The concentrations of particulate water-soluble Fe~(3+), Cu~(2+) and Co~(2+) were found in the range of 35 to 290, 42 to 462 and 0.5 to 9 ngm~(-3), respectively.