Development of a new on-line system for the sequential speciation and determination of chromium species in various samples using a combination of chelating and ion exchange resins.
A new on-line flow injection (FI) procedure for the sequential separation, preconcentration and speciation of Cr(III)/Cr(VI) species in different matrices is described based on the combining of solid phase extraction and flame atomic absorption spectrometry (FAAS). Poly 2-(5-methylisoxazol)methacrylamide-co-2-acrylamido-2-methyl-1-propanesulfonic acid-co-divinyl-benzene and Dowex 21K resins were used as chelating and ion-exchange materials for the separation/preconcentration of Cr(III) and Cr(VI) ions, respectively. Trace amounts of chromium retained on the resins were eluted sequentially with HNO3 and then introduced directly to the nebulizer-burner system of FAAS. The optimum conditions such as pH of the sample solution, amount of the resin, volume of the sample and interfering ions, which are effective on the quantitative recovery of the analytes, were investigated for sequential determination of Cr(III) and Cr(VI) ions. The preconcentration factors were found to be 48 and 30 for Cr(III) and Cr(VI), and the detection limits corresponding to three times the standard deviation of the blank (3s/b) were 0.05 and 0.3 µg L(-1), respectively. The method was verified by analyzing a certified reference material. The proposed method was applied to the determination based on the speciation of chromium in various real samples with satisfactory results.
Erciyes University, Department of Chemistry, Faculty of Arts and Sciences, TR-38039 Kayseri, Turkey.
Serkan
S
Şahan
Erciyes University, Department of Chemistry, Faculty of Arts and Sciences, TR-38039 Kayseri, Turkey. Electronic address: sacmaci@erciyes.edu.tr.
Şerife
Ş
Saçmacı
Erciyes University, Department of Chemistry, Faculty of Arts and Sciences, TR-38039 Kayseri, Turkey.
Şenol
Ş
Kartal
Bozok University, Department of Chemistry, Faculty of Arts and Sciences, TR-66200 Yozgat, Turkey.
Mustafa
M
Saçmacı
Erciyes University, Department of Chemistry, Faculty of Arts and Sciences, TR-38039 Kayseri, Turkey.
Uğur
U
Şahin
Erciyes University, Department of Chemistry, Faculty of Arts and Sciences, TR-38039 Kayseri, Turkey.
Ahmet
A
Ülgen
D000178:Acrylamides / Q000737:chemistry; D000476:Alkanesulfonates / Q000737:chemistry; D002614:Chelating Agents / Q000737:chemistry; D002857:Chromium / Q000032:analysis*; D004867:Equipment Design; D017022:Flow Injection Analysis / Q000295:instrumentation*; D006863:Hydrogen-Ion Concentration; D007475:Ion Exchange Resins / Q000737:chemistry*; D057230:Limit of Detection; D012117:Resins, Synthetic / Q000737:chemistry; D052616:Solid Phase Extraction / Q000295:instrumentation*; D013054:Spectrophotometry, Atomic / Q000295:instrumentation*; D014874:Water Pollutants, Chemical / Q000032:analysis*
D000178:Acrylamides; D000476:Alkanesulfonates; D002614:Chelating Agents; D007475:Ion Exchange Resins; D012117:Resins, Synthetic; D014874:Water Pollutants, Chemical; D002857:Chromium; C027972:Dowex; C056288:2-acrylamido-2-methylpropanesulfonate
Chelating resin; Chromium; Preconcentration; Separation; Sequential speciation