Combination of Slotted Quartz Tube Flame Atomic Absorption Spectrometry and Dispersive Liquid-Liquid Microextraction for the Trace Determination of Silver in Electroplating Rinse Bath

Abstract

Although flame atomic absorption spectrometry (FAAS) is hindered by its low sensitivity for most elements, it remains a widely used analytical technique in most laboratories. This study was aimed at mitigating the low sensitivity of an FAAS system by using dispersive liquid-liquid microextraction (DLLME) to enrich silver from aqueous solution, and enhance absorbance signals with the help of a slotted quartz tube (SQT). Three major optimization steps were carried for parameters of complexation (silver-dithizone), DLLME method and SQT apparatus. The optimum parameters/variables obtained were applied to aqueous standard solutions, and the developed calibration plots were used to validate the different systems studied. The optimized method (DLLME-SQT-FAAS) recorded an enhancement factor of 98, which correlates to detection and quantification limits of 0.60 mu g/L and 2.0 mu g/L, respectively. The optimized method was applied to an electroplating rinse solution, and close to 100% recovery results were obtained for different spiked concentrations. These results establish that the developed method can be applied to complex samples for accurate quantification of silver.