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Spectrophotometric Determination of Cadmium and Copper with

Ammonium Pyrrolidinedithiocarbamate in Nonionic Tween 80 Micellar Media

Seung Kwon Lee and Hee-Seon Choi*

Department of Chemistry, The University of Suwon, P.O. Box 77, Suwon 445-743, Korea

Received December 29, 2000

The determination of Cd2+ and Cu2+ with ammonium pyrrolidinedithiocarbamate (APDC) in Tween 80 micellar media has been studied. The UV-visible spectrum of Cd(PDC)2 complex in Tween 80 media had more sensitivity than in chloroform. Although the UV-visible spectrum of the Cu(PDC)2 complex in Tween 80 media had somewhat less sensitivity than that in chloroform, absorbance data of Cu2+ were more reproducible in Tween 80 media. The Cd(PDC)2 and Cu(PDC)2 complexes were very stable at pH 7.0 for up to 100 minutes and could be quantitatively chelated if APDC were added to the sample solution more than 30 times the moles of Cd2+ and Cu2+. The optimum concentration of Tween 80 was 0.1 %. The calibration curves of Cd(PDC)2 and Cu(PDC)2 complexes with good linearity were obtained in 0.1 % Tween 80 media. The detection limits of Cd2+and Cu2+ were 0.0493 mgmL-1 and 0.0393 mgmL-1, respectively. Recovery yields of Cd2+ and Cu2+ ions in the spiked real samples were almost 100%. Based on experimental results, this proposed method could be applied to the rapid and simple determination of Cd2+ and Cu2+ in real samples.

Keywords : Micellar media, Tween 80, Ammonium pyrrolidinedithiocarbamate, Stream water, Diluted brass sample.

http://ocean.kisti.re.kr/downfile/volume/chemical/JCGMCS/2001/v22n5/JCGMCS_2001_v22n5_463.pdf

sir can u suggest me a  method by using 5-7 dibromo 8 hydroxyquinoline. i am getting flocs in this case wot shud i do as uv detects clear liquids.