Determination of trace amounts of zirconium in real samples after microwave digestion and ternary complex dispersive liquid-liquid microextraction.

In this study, a ternary Zr(IV) system with 2-(5-bromo-2-pyridylazo)-5-diethylaminophenol (5-Br-PADAP) and fluoride was chosen on the basis of dispersive liquid-liquid microextraction method. Zirconium was extracted into the fine droplets of dichlorobenzene as extracting solvent. These drops dispersed as a cloud in the aqueous sample with the help of ultrasonic waves, and the procedure was done. Finally, atomic absorption spectrometry was applied for the determination of zirconium. The effects of different factors that influence complex formation and extraction, such as pH, amounts of complexing agents, type and volume of the extracting solvent, as well as sonication and centrifuging time, were optimized. Under optimum conditions, the calibration curve was linear in the range of 150.0-800.0 ng mL(-1) with a limit of detection of 44.0 ng mL(-1). Relative standard deviation was calculated to be 4.1 % (n = 7, c = 400.0 ng mL(-1)). The enrichment factor was 80. The proposed method was successfully used to determine the zirconium in several water, wastewater, and soil samples.