Multivariate optimization for the determination of cadmium and lead in crude palm oil by graphite furnace atomic absorption spectrometry after extraction induced by emulsion breaking
| Autor: | Leonardo S. G. Teixeira, Valdinei S. Souza, Juscelia Pereira dos Santos Alves, Gisseli Souza Valasques, Marcos A. Bezerra, Wagna Piler Carvalho dos Santos, Mirela de Jesus Santos, Ana Maria Pinto dos Santos |
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| Rok vydání: | 2020 |
| Předmět: |
Cadmium
Chromatography Materials science Trace Amounts Sonication 010401 analytical chemistry Extraction (chemistry) Aqueous two-phase system chemistry.chemical_element 02 engineering and technology 021001 nanoscience & nanotechnology Mass spectrometry 01 natural sciences 0104 chemical sciences Analytical Chemistry chemistry Emulsion 0210 nano-technology Graphite furnace atomic absorption Spectroscopy |
| Zdroj: | Microchemical Journal. 153:104401 |
| ISSN: | 0026-265X |
| DOI: | 10.1016/j.microc.2019.104401 |
| Popis: | The present work reports the development of an analytical method for the determination of trace amounts of Cd and Pb in crude palm oil using graphite furnace atomic absorption spectrometry (GF AAS) after extraction induced by emulsion breaking (EIEB). The method was based on an oil-in-water emulsion preparation to promote a high contact area between the sample drops and the acid extractant solution. Emulsification was assisted by ultrasound energy using HNO3 and Triton X-114 surfactant solutions to increase the efficiency of the extraction. Afterwards, the emulsion was broken by heating, and the acid aqueous phase in the bottom of conical glass tubes was collected for the determination of metals by GF AAS. Cadmium and lead extraction was simultaneously optimized using Doehlert design and desirability function. The best extractions were achieved using a sonication time of 18 min, a HNO3 concentration of 2.0 mol L−1 and a surfactant concentration of 4.4% (v v-1) at a breaking temperature of 90 °C. The developed method presented quantification limits of 0.17 and 0.13 μg kg−1 and precisions (repeatability,%RSD, 10.8 μg kg−1) of 1.8 and 5.4% for Cd and Pb, respectively. Addition/recovery tests gave results between 88.5% and 112%. The amounts of Cd and Pb in the analyzed samples ranged from 1.5–2.5 and 2.53–6.76 μg kg−1, respectively. |
| Databáze: | OpenAIRE |
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