Preconccntration of Cadmium Using Solid Phase Extraction by Dimethylglyoxime-Modified Silica gel and Flame Atomic Absorption Spectrophotometry Determination

摘要

This work describes the modification of silica gel with dimethylglyoxime in order to prepare an effective sorbent for the preconcentration and determination of cadmium. A new solid phase extraction method for the preconcentration of Cd(II) has been developed using a minicolumn filled with DMGMS. The best eluent was determined as hydrochloric acid and after the preconcentration process, the Cd(II) ions has been determined by FAAS. The solution pH, amount of adsorbent, the flow rate of the sample solution, type and concentration of the eluent, eluent volume and sample volume have been optimized. The effect of interfering ions on the recovery of the analytes has also been investigated. The adsorption capacities of DMGMS for Cd(II) ions was 68.49 mg g~(-1). The recoveries for Cd(II) ions under the optimum preconcentration conditions was 99±1% at the 95% confidence level. The detection limits was found as 16.8 ng mL~(-1). The developed method is applied to various real water samples. The accuracy of the method was confirmed by analyzing the certified reference material (CRM024-050).