Cathodic Adsorptive Stripping Voltammetric Determination of Molybdenum Using Mo (VI)-Cr (VI)-Pyrocatechol Violet Ternary Complex
Year: 2008
Type: article
Abstract: In this study a new selective method for determination of trace amounts of molybdenumby adsorptive stripping voltammetry at pH= 4.5 is proposed. The method is based on adsorptiveaccumulation of Mo-pyrocatechol violet (PCV) complex onto hanging mercury drop electrode(HMDE) at accumulation potential of +0.10 V (vs Ag/AgCl), followed by reduction of adsorbedspecies by voltammetric scanning in the potential range of -0.40 and 0.80 V (vs Ag/AgCl) indifferential modulation. The reduction peak current at -0.68 V (vs Ag/AgCl) is enhanced byaddition of dichromate. The effect of instrumental and chemical variable on the sensitivity of themethod were studied and optimized. In the optimum condition the limit of detection was found0.050 ng mL-1. The relationship between the peak current and molybdenum concentration islinear in the range of 1.0 – 70.0 ng mL-1. The relative standard deviations for ten replicatedeterminations of 40.0 and 25.0 ng mL-1 Mo(VI) are 0.85 and 1.3%, respectively. The effects ofinterferences ion were studied and it was found that the method is free from interferences ofsome common cations. The procedure is applied to the determination of molybdenum in realand synthetic samples with satisfactory recoveries (92.5-104%).
Institution: University of Shahrood
Language: English
Subfield: Electrochemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: diamond
OpenAlex ID: W2143193721