Spectrophotometric determination of uranium(IV) with thorin and N-hydroxy-N,N′-diphenylbenzamidine

Abstract

A simple method for the selective and sensitive spectrophotometric determination of uranium(1v) is described. The method is based on the reaction of UtV with thorin and subsequent extraction of the red-orange complex with N-hydroxy-N,N' -diphenylbenzamidine (HDPBA) in benzene as an interfacial complex at pH 2.2. The interfacial complex, dissolved in ethanol, exhibits maximum absorbance at 490 nm with a molar absorptivity of 8.8 X 104 1 mol-1 cm-1. The Sandell's sensitivity of the ternary complex is 2.7 X 10-3 pg cm-2. The system obeys Beer's law up to 2.0 pg ml-1 of UrV. Various analytical parameters were studied to establish the optimum conditions for the determination of UW. The method is selective as none of the common metal ions and anions tested interfere. The detection limit of the method is 0.09 pg ml-1 of U'". The relative standard deviation of the method for ten replicate measurements is 1.5%. The method was successfully applied to the recovery of uranium from standard ores, geological samples and synthetic matrices.

Separation Cum Pre-Concentration Technique for Determination of Uranium in Sea, Brine and Ground Water at Nano to Sub nanogram Levels

“…In this context, the authors developed a simple rapid simultaneous separation and pre-concentration method for the determination of traces of uranium in high TDS natural waters, sea, and brine water. Uranium is commonly separated and pre-concentrated by precipitation methods [9][10][11], ion exchange and chromatographic meth¬ods [12][13][14][15], extraction methods [16][17][18][19], and sorption methods [20][21][22]. Each of these methods has merits and limitations in their application.…”

Flow‐injection in‐valve solid‐phase extraction spectrophotometric determination of uranium in geological samples

“…Inductively coupled plasmamass spectrometry (ICP-MS) has been for soil samples with a sample pretreatment using solid-phase extraction [7]. Various spectrophotometric methods have been applied to geological samples such as using Arsenazo III after sample pretreatment by solvent extraction using trioctylphosphine oxide (TOPO) [8], Thorin as a color agent also with solvent extraction using N-Hydroxy-N,N-diphenylbenzamidine (HDPBA) [9], and 4-(2-pyridylazo) resorcinol (PAR) [10]. By taking advantages of flow-injection (FI) techniques, including possibility to be automated, methods based on FIA have been proposed [11][12][13][14][15].…”

Extractive Spectrophotometric Determination of Niobium (V) Using 3- Hydroxy-2-(4'-Methoxyphenyl)-4-Oxo-4H-l-Benzopyran as a Complexing Agent

“…Various existing methods [1][2][3][4][5][6][7][8][9][10][11][12][13][14] of spectrophotometric determination of niobium(V) suffer from interferences from a large number of foreign ions like Ti, V, Mo, W, Pt, Re, U and Ta. The methods are usually time consuming [1,[3][4][5], though sensitivity is slightly improved in a few cases.…”