Direct electrothermal atomic spectrometric determination of Ag in aqua regia extracts of soils, sediments, and sewage sludge with matrix modification

Abstract

Silver is subject to significant interferences caused by high chloride concentrations in electrothermal atomic absorption spectrometry, thus its direct determination in aqua regia leaches from soils, sediments, and sludges is very difficult, especially when using instrumentation equipped with deuterium-lamp background correction (D2). In this study, the interference of the aqua regia medium was successfully eliminated using Pd-citric acid chemical modifier. This chemical modifier was found to be the most advantageous in comparison with Pd mixture with ascorbic acid, tartaric acid, or citric acid-Li based on its ability to suppress the interference originating from different chloride matrix. Palladium increases the analyte stability; citric acid serves as a reducing reagent, and furthermore, it helps to remove the interfering chlorides by forming HCl, in the drying step of the electrothermal program. In the presence of the modifier, the pyrolysis temperature can be adjusted up to 1,000 °C with no loss of the analyte. The obtained limit of detection and characteristic mass were 5 ng g(-1) and 1.7 pg, respectively. The accuracy of the method was verified by means of six different reference samples and by comparing the results of the analysis of real samples with those obtained by inductively coupled plasma orthogonal acceleration time-of-flight mass spectrometer. The proposed method was applied to the Ag determination in soils, sediments, and sewage sludge samples from the Pardubice region in Czech Republic.

Direct determination of lead in bones using slurry sampling and high-resolution continuum source electrothermal atomic absorption spectrometry

“…Palladium with citric acid chemical modifier, currently being well established in our laboratory [63][64][65] , was applied to promote the thermal stabilization of the analyte. As it can be seen from Figure S7, already 1 g of Pd with 50 g of citric stabilizes Pb up to 1300° C, similarly as some of other chemical modifiers, which were previously suggested for this purpose 41,66 .…”

Mineral Nanoparticles in Waste: Potential Sources, Occurrence in Some Engineered Nanomaterials Leachates, Municipal Sewage Sludges and Municipal Landfill Sludges

“…According to the literature, these elements were considered to be the most relevant. [31][32][33][34][35][36][37]. The common range of Ag for soils is 0.01-5 mg/kg, with a representative average of 0.05 mg/kg [38], 200 times less than the mean concentration observed in the sludge.…”

“…The mean concentration of Zn is 1900 (± 1000) mg/kg sludge, 20 times more than representative concentration in soil (50 mg/kg [31], 48 mg/kg [33], range of 10-100 mg/kg in soils without natural anomaly in France [48]). The AMF of Zn is 115.…”

Direct Determination of Silver in Uranium-Zirconium-Based Metallic Fuel Using GFAAS: An Insight Into the Effect of Matrix on the Atomization of Silver

“…The use of flame and flameless AAS is reported for silver determination in wine (29), urine (30), geological and related materials (31,32), airborne particulate matter (33), lead ash and lead mud (34), biological materials (35), teeth (36), precious metals (37), blood (38), steel (39), environmental samples (40), and water samples (41).…”