چکیده:
Thallium is widely found in nature, but the only inorganic stones full of this element are crookesite and lorandit. It is
also found in pyrites of copper, lead and inorganic stones. The element and its compositions are toxic and harmful to the
environment; therefore, its application requires caution and further research. It is important to develop sensitive and
accurate analytical methods to determine trace levels of thallium in environmental and real samples. In this research,
dispersive liquid-liquid microextraction based on solidification of floating organic drop as a sample preparation method
was used for separation and preconcentration of ultra-trace amounts of thallium in soil samples prior to graphite-furnace
atomic-absorption spectrometry. Investigated effective parameters on extraction include pH, the amount of chelating
agent, type and volume of extraction solvent and extraction time. Under optimum conditions, the calibration curve was
linear in the range of 0.2-10.0 ng mL−1 of thallium in the original solution, with limit of detection of 0.03 ng mL−1. The
relative standard deviation (RSD) for ten replicated determinations of thallium ion at 5.0 ng mL−1 concentration level was
calculated as 3.3%. The proposed method was successfully applied to the determination of thallium in soil samples.
خلاصه ماشینی:
"It is important to develop sensitive and accurate analytical methods to determine trace levels of thallium in environmental and real samples.
In this research, dispersive liquid-liquid microextraction based on solidification of floating organic drop as a sample preparation method was used for separation and preconcentration of ultra-trace amounts of thallium in soil samples prior to graphite-furnace atomic-absorption spectrometry.
Keywords: Soil samples; thallium determination; dispersive liquid-liquid microextraction; graphite-furnace atomic- absorption spectrometry 1.
In this research, we coupled dispersive liquid-liquid microextraction based on solidification of floating organic drop as a sample preparation method with ultrasound for separation and preconcentration of an ultra-trace amount of thallium prior to GFAAS.
3. Results and discussion In this research, the effects of different parameters affecting complex formation and extraction conditions such as pH, amount of ligand, type and volume of extracting solvent, extraction time and interfering ions were investigated.
Conclusion Since the thallium concentration in nature is very low, and its measurement in real samples is very important due to its toxicity and harmfulness to the environment, analytical chemistry needs methods with high sensitivity and selectivity for determining and measuring this element in the environment and in real samples.
In this study, dispersive liquid-liquid microextraction based on solidification of floating organic drop prior to graphite-furnace atomic-absorption spectrometry determination, has been developed for separation and sensitive determination of thallium in aqueous samples.
Ultrasound- assisted emulsification/microextraction based on solidification of trace amounts of thallium prior to graphite furnace atomic absorption spectrometry determination."