An ICP-OES, TXRF, and EDXRF analysis of airborne particulate samples in an iron and steel smelter environment

Abstract

Elemental concentrations of air particulates collected by gravimetric method in a scrap iron and steel smelter industry were determined using a combination of four different techniques: total reflection X-ray fluorescence (TXRF), the conventional energy dispersive X-ray fluorescence (EDXRF), the modified (polarized) energy dispersive X-ray fluorescence ED(P)XRF, and the inductively coupled plasma optical emission spectroscopy (ICP-OES) analytical techniques. A number of elements were detected by all the techniques, some by one or two while some are better detected by a particular technique. The ICP-OES and TXRF techniques have low detection limits worth of consideration despite the risk of contamination possible during sample preparation. The techniques are observed to be adequate for analytes above K except for Br and Pb, which are significantly lost during digestion of samples. The Mo-target EDXRF, just like ICP-OES and TXRF, cannot detect elements below K but substitute well for them in the analysis of volatile elements like Br and Pb despite its higher detection limits for the said elements. The Mo-target EDXRF is also observed to be inadequate for rare earth elements with energies close to that of Mo as a result of possible poor resolution of the energy peaks. The ED(P)XRF is more adequate in the analysis of low Z elements as well as volatile ones. Where volatile elements like Cl, Br, and Pb and/or low Z elements are of primary interest, the use of techniques involving no elaborate sample preparation should be considered.