SIZE DISTRIBUTION AND SOLUBILITY OF 15 ELEMENTS IN ATMOSPHERIC AEROSOLS

To investigate the physical and chemical characteristics of atmospheric aerosols, aerosol particles were sampled with classifying into 13 size ranges between 0.01 and 30µm. Collected aerosol particles were separated into the soluble and insoluble components. The concentrations of 15 elements in both components were determined by a PIXE analysis using a 2.0MeV-proton beam.

The mass size distribution of each element was illustrated in three types: mono-modal distribution having only one peak in the fine or coarse fraction and the bimodal distribution having one peak each in fine and coarse fractions. The mass mean diameter of 15 elements ranged between 0.62µm of S and 3.15µm of Fe. More than 85% of atmospheric aerosols consists of the lighter elements such as C, N, O, H and Al. The soluble component was dominant in the smaller size range and the insoluble component in the larger size range. Si, Ti and especially Fe existed in high insoluble state. Conversely, Ca, Zn, Br and especially S and Cl were dissolved in water.