Real-Time Determination of Anions and Cations in Aerosols by Ion Chromatography

摘要

Research on air pollution requires rapid and accurate measurements of inorganic species in ambient air. Coupling a Particle-lnto-Liquid-Sampler (PILS) to Metrohm's 850 Professional IC allows for quasi-continuous measurements with an unprecedented temporal resolution of just 5 to 15 minutes. The determination of anions and cations in atmospheric aerosols yields essential information concerning atmospheric transport and transformation processes. Until now these determinations have been carried out using filters. However, this method only allows one to determine averages over a time span of 24 hours or even more. Moreover, the results can be compromised by desorption processes and chemical transformations. In contrast to sampling devices relying on filters, using a PILS allows semi-continuous sampling of aerosols downstream from a denuder system. Subsequent to the removal of interfering gas-phase species, the remaining aerosol particles are dissolved into water phase by means of supersaturated steam.