Kinetic Spectrophotometric Determination of Traces of Molybdenum(VI) by Its Inhibitory Effect on the Oxidation of 4-Hydroxycoumarine by Potassium Permanganate

Abstract

The present paper describes a simple, selective and sensitive kinetic method for the determination of trace amounts of molybdenum(VI) based on its inhibitory effect on the reaction oxidation of 4-hydroxycoumarine by KMnO4 in the presence of hydrochloric acid, at pH 1.75 at 25˚C. The rate of the indicator reaction was followed spectrophotometrically by measuring the decrease in the absorbance of KMnO4 at 525 nm. The development method includes optimization of the reagent concentration and temperature. The calibration graph was linear in the range of concentrations from 20 to 200 ng/cm 3 of molybdenum(VI). The probable relative error was in the interval 3.10 -10.52% for the concentration range of 200 -20 ng/cm 3 molybdenum(VI), respectively. The interference effects of the foreign ions were determined to assess the selectivity of the method. The developed method was found to have relatively good selectivity, sensitivity, simplicity and rapidity. The proposed method was applied to the determination of molybdenum(VI) in a particular type of steel and alloy (hastelloy).

Development and use of the kinetic method for determination of trace amounts of vanadium (V) in water samples from objects of the environment

“…Then these samples were subjected to a recommended kinetic procedure for determination of vanadium (V) [24]. RESULTS AND DISCUSSION Permanganate as an indicator substance (λ max = 525 nm) is widely used in different spheres, in particular for preventing pollution and monitoring of the environment [18][19][20]. A dissolving substance (4 OH coum) and its colorless solution are used in pharmacotherapy (chemotherapy).…”

“…Constant (at fixing time) photometric method was used for processing kinetic data. When using the said method for determination of vanadium (V) in different samples of water, compounds of Mn, Mo, Au [18][19][20] interfere; their influence may be eliminate by means of masking ligands. EXPERIMENTAL Spectrophotometric measurements were conducted on a Perking Elmer Lambda device with thermo stated cylindrical cells (10 cm long).…”

A Sensitive, Selective New Analytical Reagent, 2, 6-Diacetylpyridine bis-4-phenyl-3-thiosemicarbazone for Extractive Spectrophotometric Determination of Mo(VI) in Food Samples

“…Molybdenum is a transition element, which can exist in several oxidation states ranging form 0 to VI, where VI is the most common form found in agricultural soils (Kaiser et al 2005). Molybdenum is a bioessential element and its occurrence in water samples is of interest from both environmental and chemical points of view (Micic et al 2006). Molybdenum is commercially important in metallurgical and agricultural laboratories.…”