Analysis of heavy metals in liquids using Laser Induced Breakdown Spectroscopy by liquid-to-solid matrix conversion

Laser Induced Breakdown Spectroscopy has been applied to the analysis of heavy metals in liquid samples, an issue of major importance for environmental monitoring. In this work, a new approach was developed in which liquid solutions were converted into solid pellets of calcium hydroxide by mixing with CaO. Therefore, liquid sample analysis is replaced by solid matrix analysis, overcoming the well-known difficulties and drawbacks of the analysis of liquid samples, and providing additional advantages with respect to other experimental setups. The plasma was produced in air at atmospheric pressure, by a pulsed Nd:YAG laser. Analytical results were achieved for Cr, Pb, Cd and Zn through calibration curves and limits of detection.