Preconcentration and Determination of Trace Copper(II) and Lead(II) in Aqueous Solutions by Adsorption on Ca-Alginate Bead

Department of Chemical Engineering, Samcheok National University, Samcheok, Gangwon 245-711, Korea(Received October 11, 2004) . Cu(II) Pb(II) . Ca(II) . pH, Ca(II) , , , . Cu(II) Pb(II) Ca(II) pH 5.0 , . , . , 1.0 mol/L . Na(I), K(I) Mg(II) Pb(II) Cu(II) . 2 90.4~104.3% Cu(II) Pb(II) . : , , , (II), (II)ABSTRACT. The preconcentration and determination of trace Cu(II) and Pb(II) on calcium alginate beads in aqueous solu-tion were studied. A calcium alginate beads were prepared by adding an alginic acid to sample solution contained Ca(II). Somefollowing conditions were optimized: the pH of sample solution, amount of alginic acid, and stirring time for effective adsorp-tion; the type and concentration of acid, and sonication time in an ultrasonic vibrator for the perfect de-sorption. A sample solu-tion was prepared with Cu(II) and Pb(II) in DI water. And Ca(II) and ethanol was added into the sample solution. The pH ofthe final sample solution was controlled with buffer solution. The alginic acid were dispersed in the sample solution by a mag-netic stirrer. This mixture was stored in room temperature for 30 min to form a calcium alginate. After the beads were filteredand washed on a membrane filter, the analytes were redissolved from the beads by an ultrasonic vibration of 10 minutes in 1.0MHNO