On-line Preconcentration of Pd(II) Using Polyamine Silica Gel Filled Mini Column for Flame Atomic Absorption Spectrometric Determination

In this study, a novel method for determination of Pd(II) ions at trace level was developed using on-line preconcentration onto polyamine group bonded silica (PA-SG) with flame atomic absorption spectrometric determination. Pd(II) uptake dynamics of PA-SG was studied batchwise by investigating acidity and chloride concentration of aqueous phase, contact time and initial concentration of Pd(II) ions. The Pd(II) adsorption capacity of PA-SG was found to be 158.7 mg g(-1) from aqueous phase containing 0.1 M HCl. The on-line preconcentration procedure of Pd(II) was optimized with main analytical parameters including sample and eluent flow rate, eluent type and volume and matrix ions. The optimum eluent type and flow rate of sample and eluent were found to be 1.0% thiourea in 1.0 mol L-1 HCl and 7.5 mL min(-1), respectively. The preconcentration factor and sampling frequency were calculated to be 23.9 and 20 h(-1), respectively. The calibration graph was linear over the range 10-200 mu g L-1. The limits of detection (3 sigma) and quantification (10 sigma) values were computed to be 3 mu g L-1 and 10 mu g L-1, respectively. The RSD, % was found to be 4.6% for five measurement of 25 mu g L-1 of Pd(II) ions. The accuracy of the developed method was successfully checked by determination of Pd(II) level of certified reference material platinum ore (SARM 7B). The proposed method was successfully applied for Pd(II) determination in various environmental water samples such as river, lake, sea and tap water, and spent auto catalyst.