ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

A straightforward deep eutectic solvent-based extraction for the determination of lead in drill cuttings by graphite furnace atomic absorption spectrometry

Caroline Gonçalves, Bruno Luís Ferreira, Elenice Hass Caetano Lacerda, and Eduardo Sidinei Chaves

Chemistry Department, Campus Trindade, Federal University of Santa Catarina, Florianópolis, Brazil

E-mail: f.bruno@outlook.com

Received: 20 December 2023  Accepted: 23 April 2024

Abstract:

An environmentally friendly method was developed using deep eutectic solvent ultrasound-assisted extraction procedure (DES-UAE) for Pb determination in drill cuttings (DC) by graphite furnace atomic absorption spectrometry (GF AAS). In this study, 50 mg of the DC samples in 2.50 g of diluted DES (30% w/w of water) was subjected to UAE at 80 ± 5 °C for 50 min. The extraction parameters, temperature, time, and percentage of water in the DES, were evaluated using a Box–Behnken experimental design. Lead was determined by GF AAS, using Pd as a chemical modifier, 900 °C of pyrolysis, and 2100 °C of atomization temperatures. The results demonstrated that DES composed of choline chloride and oxalic acid (1:1 molar ratio) combined to UAE, showed greater Pb extraction efficiency. The precision (RSD < 3.8), the respective limits of detection and quantification (0.2 and 0.6 µg g⁻¹), were suitable for Pb determination in DC. The method’s accuracy was evaluated through the analysis of certified reference materials and by comparing the results with those obtained by ICP-MS analysis after acid digestion and  no significant difference was observed (at 95% confidence level). The DES-UAE was applied to determine Pb in DC from different depths, with Pb concentration  ranging from 1.14 to 6.13 and 1.64 to 168.4 µg g⁻¹ for samples from onshore and offshore wells, respectively.

Graphical abstract

Keywords: Deep eutectic solvent; Ultrasound-assisted extraction; Potentially toxic elements; GF AAS; Green chemistry

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-024-03482-7

Chemical Papers 78 (9) 5433–5444 (2024)