Author(s)

Sayed Zia Mohammadi, Mohammad Ali Karimi, Ali Shiebani, Laleh Karimzadeh

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In the present work, a ultrasound-assisted emulsification dispersive liquid-liquid microextraction based on solidification of floating organic droplet method has been developed as a sample preparation method prior to flame atomic absorption spectrometry determination of trace amounts of gold in the standard, wastewater and river water samples. In the proposed method, 1-dodecanol and 5-(4-dimethylamino-benzylidene) were used as extraction solvent and chelating agent, respectively. Several factors that may be affected on the ex-traction process, such as type and volume of the extraction solvent, ionic strength, pH of the aqueous solu-tion, extraction temperature and extraction time were studied and optimized. Under the best experimental conditions, the calibration curve exhibited linearity over the range of 8.0 ng●mL^-1- 3.0 µg●mL^-1 with a correlation coefficient of 0.9978 and detection limit based on three times the standard deviation of the blank signal was 1.5 ng●mL^-1. Eight replicate determinations of 0.2 and 1.0 μg●mL^-1 of gold gave a mean absorbance of 0.051 and 0.253 with relative standard deviations of ±2.3% and ±1.5%, respectively. Finally, the developed method was successfully applied to the extraction and determination of gold ions in a silica ore, wastewater, river water and standard samples and satisfactory results were obtained.

Ultrasound-Assisted Emulsification, Microextraction, Solidification, Floating Organic Droplet, Preconcentration, Gold Determination, Silica Ore

S. Mohammadi, M. Karimi, A. Shiebani and L. Karimzadeh, "Ultrasound-Assisted Emulsification Dispersive Liquid-Liquid Microextraction Based on Solidification of Floating Organic Droplet for Separation of Trace Gold Prior to Flame Atomic Absorption Spectroscopy Determination," American Journal of Analytical Chemistry, Vol. 2 No. 2, 2011, pp. 243-249. doi: 10.4236/ajac.2011.22029.