Direct Determination of Copper in Solids by Direct Current Argon Plasma Emission Spectrometry with Sample Introduction Using Laser Ablation

Abstract

A direct-current argon plasma emission spectrometric system with sample introduction using laser ablation has been developed and evaluated for the determination of copper in pelletized powder and solid samples. The use of a low-energy and high-repetition-rate Nd: YAG laser gave a nearly steady-state signal that could be integrated over a relatively long time period of 30 s. This allowed a larger portion of the sample to be probed, and high % RSD—often obtained with single shot laser ablation because of sample inhomogeneities—reduced to 2–6%. The emission intensity was dependent on sample preparation technique, particle size, laser pulse rate, and copper anion. The system was used to directly determine copper in pelletized ore samples with 2–6% RSD, a detection limit of 20 μg g−1, and acceptable accuracy, once the factors described above were controlled.