Preconcentration of Palladium in Aqueous Samples Using a Surfactant‐Coated Alumina Modified with Thioridazine · HCl and Its Determination by Atomic Absorption Spectrometry

Abstract

A selective, simple, and reliable technique for the separation, preconcentration, and determination of trace amount of palladium has been developed using a modified sodium dodecyl sulfate (SDS)‐coated alumina solid phase. The effect of pH, flow rate of sample solution and eluent, and foreign ions on the sorption of palladium by this sorbent have been investigated. By the passing of 500 mL aqueous samples (pH 1–3) of palladium containing 20 µg palladium through a 1.5 g surfactant‐coated alumina microcolumn immobilized with 1 mg thioridazine · HCl (TRH), Pd(II) ions adsorb quantitatively and most elements will pass through the column to drain. The retained Pd(II) ions are then stripped from the microcolumn with 2 mL of 2 M HClO₄ in acetylacetone and determined by the flame atomic absorption spectroscopy (FAAS). The proposed method permitted large enrichment factors of about 250 and higher. The relative standard deviation (five replicate analysis) at 0.4 and 1 µg mL⁻¹ levels were 0.7% and 1.2%, respectively. The method was applied to the recovery of Pd(II) ions from different synthetic samples.

Keywords:

• Preconcentration
• Palladium
• Surfactant‐coated alumina
• Thioridazine · HCl

Acknowledgments

Financial support from the Research Affairs of Urmia University is acknowledged. The authors are grateful to the PARS‐MINOO Pharmaceutical Company, Tehran, Iran for the supply of working standard thioridazine · HCl.