Solid phase extraction of lead in water using triethylenetetramine-modified resin for determination by UV-visible and atomic spectrometries

Abstract

Polystyrene-divinylbenzene contained triethylenetetramine (TETA-PS-DVB) was successfully prepared by two-step reaction and employed as sorbent in solid phase extraction (SPE) of Pb(II) before its determination by UV-visible spectrometry and flame atomic absorption spectrometry (FAAS). The sorption performance of Pb(II) in single metal solution was similar to that obtained by binary metal solutions (Pb(II) with Co(II), Cr(II), Cu(II), Ni(II), and Zn(II)) indicating the high selectivity of the sorbent. Under optimal conditions, 60 minutes were utilized for adsorption of Pb(II) on the sorbent in batch method and the kinetics of sorption fitted well with pseudo-second order rate. The maximum sorption capacity calculated from Langmuir adsorption isotherm was found to be 4.04 µmol/g. The suitable desorption solution and elution time for determination by FAAS were 10% (v/v) HNO3 and 30 minutes, respectively. While, the determination by UV-visible spectrometry was successful using saturated dithizone in 7% (v/v) triton X-100 solution and controlling the pH at 5.5 by acetate buffer solution. The method could be applied for the extraction of Pb(II) in cement-base leachate with the percentage recoveries of 81 to 84 and 81 to 86 for determination by FAAS and UV-visible spectrometry, respectively. The relative standard deviation for determination by FAAS and UV-visible spectrometry were 2.19% and 2.58%, respectively. The extraction in column method showed unsatisfied low extraction percentage suggesting that the solid phase was not suitable for using in column mode. The used solid phase was unable to be reused.