Direct analysis of hexavalent chromium in water samples by UV-Vis spectrophotometry: Effects of pH and the presence of foreign ions

Volume 7, Issue 02, Pages 18-28, Jun 2024 *** Field: Analytical Chemistry

  • Rayane Nadjet Fassi Laboratory of Pollution and Water Treatment, Chemistry Department, University Brothers Mentouri Constantine 1, Constantine, Algeria
  • Chahrazed Boukhalfa, Corresponding Author Laboratory of Pollution and Water Treatment, Chemistry Department, University Brothers Mentouri Constantine 1, Constantine, Algeria
Keywords: Analytical method, Chromium (VI), UV-Vis spectroscopy, Water samples


The present study aims to characterize the direct UV-Vis spectrophotometric analysis of hexavalent chromium (CrVI) in aqueous solution. The effects of pH and the presence of different ions are evaluated. The results obtained show that at pH ≤ 6, Cr(VI) analysis must be carried out at 350 nm. The Beer-Lambert law is respected for a concentration lower than 100mg Cr(VI) L-1. At pH ≥ 8, the analysis must be performed at 372 nm. In this case, the linearity range of the standard curve does not exceed the concentration of 25 mg Cr(VI) L-1. In the pH range 6 <pH < 8, the direct Cr(VI) analysis cannot be performed. Whatever the pH of the solutions, the presence of acetate, oxalate, citrate, and tartrate with a concentration ten times higher than that of Cr(VI), has no effect. At pH 2, only the presence of Fe(II) and Fe(III) ions prevents the direct determination of Cr(VI) ions. In the presence of metallic ions [Mn(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II)), Cr(VI)] analysis must be carried out at pH 2. At higher pH, these ions have a significant effect.


N. Esmaeili, J. Rakhtshah, E. Kolvari, H. Shikhanoo, Ultrasound assisted-dispersive-modification solid-phase extraction using task-specific ionic liquid immobilized on multiwall carbon nanotubes for speciation and determination mercury in water samples, Microchem. J., 154 (2020) 104632.

H. Shikhanoo, M. Habibnia, A. Rashidi, A. Faghihi Zarandi, Simultaneously speciation of mercury in water, human blood and food samples based on pyrrolic and pyridinic nitrogen-doped porous, graphene nanostructure, Food Chem., 403 (2023) 134394.

T. W. Clarkson, Molecular and ionic mimicry of toxic metals, Ann. Rev. Pharmacol., 33 (1993) 545-571.

K. Shil, S. Pal, Metabolic adaptability in hexavalent chromium-treated renal tissue: an in vivo study, Clin. Kidney J., 10 (2017) 1-8.

R. M. Park, J. F. Bena, L. T. Stayner, R. J. Smith, H. J. Gibb, P. S. Lees, Hexavalent chromium and lung cancer in the chromate industry: a quantitative risk assessment, Risk Anal., 24 (2004) 1099-1108.

P. Cazeneuve, Sur la diphénylcarbazide, réactif très sensible de quelques composés métalliques; cuivre, mercure, fer, acide chromique, Bull. Soc. Chim., 23 (1900) 701-706.

A. Wiryawan, R. Retnowati, P. Burhan, S. Syekhfani, Method of analysis for determination of the chromium (cr) species in water samples by spectrophotometry with diphenylcarbazide, J. Environ. Eng. Sustain. Technol., 5 (2018) 37-46.

A. Lace, D. Ryan, M. Bowkett, J. Cleary, Chromium monitoring in water by colorimetry using optimized 1,5-Diphenylcarbazide method, Int. J. Environ. Res. Public Health, 16 (2019) 1803-1818.

A. Oumedjbeur, O. Thomas, Dosage rapide du chrome (VI) dans les eaux naturelles, Analusis, 17 (1989) 221-224.

M. C. Fournier-Salaün., P. Salaün, Quantitative determination of hexavalent chromium in aqueous solutions by UV-Vis spectrophotometer, Cent. Eur. J. Chem., 5 (2007) 1084-1093.

O. Thomas, S. Gallot, E. Naffrechoux, Ultraviolet multiwavelength absorptiometry (UVMA) for the examination of natural waters and wastewaters, Part III. Determination of Chromium(VI), Fresenius J. Anal. Chem., 338 (1990) 241-244.

A. Sanchez-Hachair, A. Hofmann, Hexavalent chromium quantification in solution: Comparing direct UV–visible spectrometry with 1,5-diphenylcarbazide colorimetry, C. R. Chim., 21 (2018) 890-896.

D. Kim, J. Om, Direct spectroscopic determination of aqueous phase hexavalent chromium, Univers. J. Eng. Sci., 1 (2013) 1-4.

M.M. Eskandari, Cloud point assisted dispersive ionic liquid-liquid microextraction for chromium speciation in human blood samples based on isopropyl 2-[(isopropoxycarbothiolyl) disulfanyl] ethane thioate, Anal. Chem. Res., 10 (2016) 18-27.

A. Khaligh, F. Golbabaei, A Vahid, On-line micro column preconcentration system based on amino bimodal mesoporous silica nanoparticles as a novel adsorbent for removal and speciation of chromium (III, VI) in environmental samples, J. Environ. Health Sci. Eng., 13 (2015) 47.

A.A.Miran Beigi, M.M. Eskandari, Dispersive liquid-liquid microextraction based on task-specific ionic liquids for determination and speciation of chromium in human blood, J. Anal. Chem., 70 (2015) 1448-1455.

H.Z. Mousavi, Chromium speciation in human blood samples based on acetyl cysteine by dispersive liquid–liquid biomicroextraction and in-vitro evaluation of acetyl cysteine/cysteine for decreasing of hexavalent chromium concentration, J. Pharm. Biomed. Anal., 118 (2016) 1-8.

M. Arjomandi, A review: analytical methods for heavy metals determination in environment and human samples, Anal. Methods Environ. Chem. J., 2 (2019) 97-126.

A. Rouhollahi, Preconcentration and determination of heavy metals in water, sediment and biological samples, J. Serb. Chem. Soc., 76 (2011) 1583-1595.

JD. Ramsey, L. Xia, MW. Kendig, RM. McCreery, Raman spectroscopic analysis of the speciation of dilute chromate solutions, Corros. Sci., 43 (2001) 1557-1572.

How to Cite
Fassi, R. N., & Boukhalfa, C. (2024). Direct analysis of hexavalent chromium in water samples by UV-Vis spectrophotometry: Effects of pH and the presence of foreign ions. Analytical Methods in Environmental Chemistry Journal, 7(02), 18-28.
Original Article