Method development for the determination of chlorine by high-resolution graphite furnace molecular absorption spectrometry via GaCl

Abstract

Abstract In this study, a method was developed for the determination of chlorine via molecular absorption of GaCl at 249.060 nm generated in a graphite furnace of a high-resolution continuum source atomic absorption spectrometer. For this purpose, 25 μg of Ga and standard solutions or samples were mixed on the platform. The optimized pyrolysis and vaporization temperatures were 500 and 1100 °C, respectively, which were uncommonly low compared to other diatomic molecules between chlorine and molecule forming reagents of chlorine and non-metals. The limit of detection for the method was 2.3 ng which was sufficient to determine chlorine in samples to be analyzed in this study as well as in many matrices. The Cl concentration was determined in uncertainty limits of a certified wastewater sample. Finally, Cl concentrations in some milk and mineral water samples were determined using aqueous standards for calibration. The results were compared with those found by analyte addition technique and no significant difference was found.