Simultaneous Spectrophotometric Determination of Cr(Ⅲ) and Cr(Ⅳ) in Chromium Plating Solution via Flow-Through Analysis

흐름계를 이용한 크롬도금 용액의 Cr(Ⅲ)와 Cr(Ⅵ)의 분광학적 동시 분석 방법

  • Kim, Sun Kwan (Department of Chemistry, Kwang Woon University) ;
  • Nam, Hakhyun (Department of Chemistry, Kwang Woon University) ;
  • So, Jae Chun (Research Institute of industrial Science & Technology) ;
  • Lee, Won (Research Institute for Basic Sciences and Department of Chemistry, Kyung Hee University) ;
  • Cha, Geun Sig (Department of Chemistry, Kwang Woon University) ;
  • Han, Sang Hyun (Department of Chemistry, Kwang Woon University)
  • 김선관 (광운대학교 이과대학 화학과) ;
  • 남학현 (광운대학교 이과대학 화학과) ;
  • 소재춘 (포항제철 주식회사 산업과학기술연구소) ;
  • 이원 (경희대학교 기초과학연구소, 문리과대학 화학과) ;
  • 차근식 (광운대학교 이과대학 화학과) ;
  • 한상현 (광운대학교 이과대학 화학과)
  • Published : 19950200

Abstract

The amount of Cr(Ⅲ) and Cr(Ⅵ) in a chromium plating solution could be determined simultaneously within five minutes using UV/VIS spectrophotometer coupled with a flow-through analysis(FTA) setup. The λmax's at 580 nm and 440 nm which correspond to Cr(Ⅲ) and Cr(Ⅵ), respectively, well obey the Beer-Lambert law in the range over 0.05 g/L for Cr(Ⅲ) and 0.005 g/L for Cr(Ⅵ). when the pH of the sample is less than 4.0, the absorption extinction coefficients of those peaks are not much dependent on the proton concentration. The amount of Cr(Ⅲ) and Cr(Ⅵ), and the total chromium in post treatment chromium plating solution, which normally has few g/L of Cr concentration, could be easily measured using UV/VIS spectrophotometry after the sample had been diluted with sulfuric acid of pH=1.0 in the flow-through analysis setup; this method is far more convenient and faster than the common redox titration (which requires at least 40 min/sample) method, while the accuracy of the method is highly comparable to conventional titrimetric method. Since the implementation of an PTA-UV/VIS setup in any plating industry is cost effective and easy to operate, the analytic method described in this paper may be applied directly for in situ analysis of plating solutions.

Keywords

References

  1. The Canning Handbook on Electroplating W. Canning Ltd.
  2. Mordern Analysis for Electroplating Wild, P.
  3. Chronium Plating Weiner, I. R.;Walmsley, A.
  4. Anal. Chim. Acta v.174 Whitaker, M. J.
  5. Mikrochim. Acta v.Ⅱ Shofstahl, J. H.;Keck, L.;Hardy, J. K.
  6. Quantitative Chemical Analysis Kolthoff, I. M.;Sandell, E. B.;Meehan, E. J.;Bruckenstein, S.
  7. Anal. Chim. Acta v.215 Clark, B. R.;DePaoli, D.;McTaggart, D. R.;Patton, B. D.
  8. Anal. Chim. Acta v.196 Ruz, J.;Rios, A.;Luque, de Castro, M. D.;Valcarel, M.
  9. Anal. Chem. v.58 Pratt, K. W.;Koch, W. F.
  10. Z. Anal. Khim. v.46 Granzhan, A. V.;Charykov, A. K.
  11. Z. Anal. Khim. v.41 Tsygankof, A. M.;Kuznetsov, V. V.;Tarasova, N. P.;Yagodin, G. A.;Zhukov, A. F.;Urusov, Y. B.
  12. RIST 硏究技報 v.4 Kim, S. H.;Park, C. S.;Lee, S. W.
  13. Electroplating Engineering Handbook Graham, A. K.;Pinkerton, H. L.
  14. Mikrochim. Acta v.Ⅲ Srivastava, S. K.;Singh, A. K.;Garg, M.;Khanna, R.