A simple LIBS method for fast quantitative analysis of fly ashes

An evaluation of quantitative analysis of major elements (Ca, Al, Mg, Si and Fe) present in fly ashes was made using a simple and cost effective LIBS system. LIBS parameters were optimized to obtain best sensitivity and repeatability. In this purpose different binders were compared, leading to best sensitivity and mechanical stability when a binder containing silver and cellulose was employed in a 1:1 mass ratio.In order to be able to determine major elements in different fly ashes, a multi-matrix calibration was employed. Four reference materials were employed for calibration and five other fly ashes were selected as sample. Concentrations obtained by LIBS were compared to wet acid digestion and alkali fusion followed by ICP-OES analysis. Ca, Mg, Fe, Si and Al concentrations found using the LIBS method developed were in a good agreement with the values obtained by classical methods.