Download Center

Determination of Chromium (VI) by Adsorptive Stripping Voltammetry with Morin
Natural Sciences & Environment Journal (NSEJ), Volume 2, Jul 2017

View Abstract   Hide Abstract
Redox speciation of chromium has attracted a great deal of interest in view of the toxic properties of Cr(VI) compared with the much less toxic Cr(III). Cr(VI) dominates in effluents from metallurgical and metal finishing industries and Cr(III) exists mainly in tannery, textile and decorative plating industry wastes. The total chromium concentration in unpolluted natural waters is 1-10 ^g L-1 1. A procedure for the determination of chromium in contaminated waters by AdSV using morin or morin-5-sulfonic acid as adsorbing and complexing agents have been optimized. Cr(VI)-morin complexes are adsorbed into electrode and then reduced to Cr(III)-morin complexes. In the presence of tetrabutylammonium tetrafluoroborate peak current of free ligand decreases and the peak current of complex were lightly enhanced. The variation of peak current with pH, adsorption time, adsorption potential, ligand and quaternary ammonium salt concentration, and some instrumental parameters such as stirring rate in the accumulation stage and step amplitude, pulse amplitude and step duration in the obtaining of the square wave voltamperograms were optimized. The best experimental parameters were pH = 4.0 - 8.0 (Britton Robinson buffers), Cmomi = 3.5 |imol L-1, CTBATFB = 10.0 |i mol L-1, tads = 60 s and Eads = -0.50 V vs Ag/AgCl. Under these conditions the peak current was proportional to the chromium concentration over the 0.0-25.0 |ig L-1 range, with a detection limit of 0.7 |ig L-1. Reproducibility for 6.0 |ig L-1 chromium solution was 3.1 % (n = 6). The method was validated with synthetic sea water spiked with 22 metal ions and fortified water GBW08607 (Reference material. Certified value: Cr 0.500|ig/g) and applied to analysis of Cr(VI) in the presence of Cr(III) in contaminated waters.

Author(s): Veronica Arancibia, Cesar Gonzalez, Manuel Zuniga and Edgar Nagles
Choose an option to locate/access this article/journal

Check if you have access through your login credentials or your institution

Members Login Panel

To Complete the Process of Article Purchasing, Please click on Payment Button. You can make a credit card payment through the highly secure payment system, you can now pay your bill online 24 hours a day;



Click on the above icon to go to the OASP Web-based Submission System


The process of peer review involves an exchange between a journal editor and a team of reviewers, also known as referees. A simple schematic of OASP's Peer-Review process has been shown in this section.