QD98 : Determination of trace amounts of silver by 1-phenyl-1,2-propanedione-2-oximethiosemicarbazone as complexing agent and using dispersive liquid-liquid microextraction–flame atomic absorption spectrometry
Thesis > Central Library of Shahrood University > Chemistry > MSc > 2011
Authors:
Mohammad Sarikhan Kheljani [Author], Naser Goudarzi[Supervisor], Mansour Arab Chamjangali[Supervisor]
Abstarct: In this study, a simple, sensitive and rapid method of dispersive liquid-liquid microextraction (DLLME) was proposed for preconcentraton of silver prior determination by flame atomic absorption spectrometry (FAAS). In this method, silver ions reacted with 1-phenyl-1,2-propanedione-2-oximethiosemicarbazone (PPDOT) and complex formation was occured. Then, a mixture of extraction and disperser solvents with optimized volume ratio was injected into the aqueous sample and the complex was extracted into the interior of the droplets of the extraction solvent. After centrifugation, the organic phase containing silver ions was sedimented and two phases were separated and then the organic phase was diluted and the amounts of silver were determined by atomic absorption spectrometry. In this work, chloroform and methanol were used as extraction solvent and disperser solvent, respectively. The effects of different parameters such as pH, type and volume of buffer, type and volume of extraction solvent, type and volume of disperser solvent, ligand concentration, volume of aqueous sample, extraction time, centrifugation time and ionic strength were investigated. Also, the effects of foreign ions were investigated. Under the optimized conditions, a linear calibration curve in the range of 0.0060-0.12 mg.L-1, with detection limit of 0.61 µg.L-1 and enrichment factor of 35.5were achieved. The relative standard deviations (RSD %) for six replicate determinations of 0.0080, 0.0200 and 0.1000 mg.L-1 of silver(I) were 2.53,1.48 and 2.49%, respectively. This method was successfully applied for determination of silver(I) in the real samples.
Keywords:
#silver #1-phenyl-1 #2-propanedione-2-oximethiosemicarbazone #dispersive liquid-liquid microextraction #flame atomic absorption spectrom Link
Keeping place: Central Library of Shahrood University
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