Progress in arsenic determination at low levels in copper ores by laser-induced breakdown spectroscopy

Abstract

Arsenic determination by LIBS at low levels is a challenging analytical task due to its low sensitivity, limited number of available emission lines, and spectral interferences. In this work, a LIBS system with controlled atmosphere for the determination of arsenic at low concentrations in copper ores is presented. Under optimized conditions, the As lines at 278.06 nm (with interference of Fe II) and 286.04 nm were able to be used for measurements. Improved analytical figures of merits were obtained using deconvoluted spectra and artificial neural network based on a radial basis function (ANN-RBF), specific values of relative error percentage (REP %), root mean square error of prediction (RMSEP) and intervals of limits of detection (LOD) and quantification (LOQ) were 18.6 wt%, 0.037 wt%, 0.045–0.062 wt% and 0.135–0.185 wt%, respectively.