فهرست نشریات علمی دسترسی آزاد ایران

Thallium is widely found in nature, but the only inorganic stones full of this element are crookesite and lorandit. It isalso found in pyrites of copper, lead and inorganic stones. The element and its compositions are toxic and harmful to theenvironment; therefore, its application requires caution and further research. It is important to develop sensitive andaccurate 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 methodwas used for separation and preconcentration of ultra-trace amounts of thallium in soil samples prior to graphite-furnaceatomic-absorption spectrometry. Investigated effective parameters on extraction include pH, the amount of chelatingagent, type and volume of extraction solvent and extraction time. Under optimum conditions, the calibration curve waslinear 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. Therelative standard deviation (RSD) for ten replicated determinations of thallium ion at 5.0 ng mL−1 concentration level wascalculated as 3.3%. The proposed method was successfully applied to the determination of thallium in soil samples.