Quantification of Inorganic Elements in Aerosol Samples by Inductively Coupled Plasma-Atomic Emission Spectrometry with Alkali Melting

In atmospheric particles (TSP and PM₁₀), the high contents of some inorganic elements including Si, Al, Ca, Mg, K, Fe and Na are the proxy elements for the particles source analysis. At present, there are several methods to analyze inorganic elements for atmospheric particles such as neutron activation analysis, X-ray Fluorescence Spectrometry (XRF), Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES) and Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) after dissolving by microwave (or high-pressured cauldron). The established method for determining Si, Al, Ca, Mg, Fe, Ti, Sr, Ba and Zr in aerosols by ICP-AES with alkali melting solved the problems of incomplete dissolving for Si caught in an atmospheric particles filter diaphragm, and improved the precision and accuracy of the determinations of major and trace elements such as Ti, Ba, Sr, Zr. In the paper, the formula of flux is also discussed, the temperature and time for ashing, acidity, and interference effect. This method was developed by ashing the samples at a temperature of 530-550℃ for 60 min in a nickel crucible with sodium hydroxide, extracted by hot water, acidificated by 2 mL HCl (50%), eliminated interference by sodium-matrix-matching and measured by ICP-AES. The results were in good agreement with certified values with an accuracy of RE<4%, precision of<5% and detection limits of 0.0047-1.2 ng/g under the selected experimental conditions. This method is inexpensive, rapid, convenient and suitable for a large number of bulk samples with high accuracy and precision.