A. B. Farag

Iodometric microgram determination of Mn (II) in aqueous media by an indirect chemical amplification reaction

A rapid, simple and highly sensitive iodometric amplification method is described for the determination of microgram amounts of Mn(II). The method is based on oxidation of Mn(II) with an excess of periodate in acetate buffer (pH 2.8-3.0), masking of the unreacted periodate with molybdate, and after addition of iodide, titration of the liberated iodine is with thiosulphate. The proposed method offers 20-fold amplification for Mn(II) and was found suitable for the determination of Mn(II) in the presence of permanganate ions. Mn(II) in tap water and an industrial waste water has been successfully determined by the proposed method.

Iodometric microgram determination of chromium(III) and (VI) by use of chemical amplification reactions

A simple, rapid and sensitive method is described for the iodometric determination of microgram amounts of chromium(III), based on the oxidation of chromium(III) with periodate at pH 3.2, removal of the unreacted periodate by masking with molybdate and subsequent iodometric determination of the liberated iodate. Chromium(VI) can be determined by this method after prior reduction to chromium(III) with sodium sulphite. The method can also be used for the analysis of organochromium compounds.

Trace Analysis by Direct Spectrophotometric Measurements on Polyurethane Foam. Determination of Chromium (VI) as Blue Perchromic Acid with Unloaded & Tri-n-Butylphosphate Loaded Foam

Abstract The formation of blue perchromic acid represents one of the most sensitive and selective tests for the identification of chromium. The sorption of perchromic acid on TBP loaded foam has been investigated for the detection, semiquantitative and quantitative determinations of chromium (VI). In foam batch method, it was possible to detect as los as 0.6, 0.4 and 0.2 ppm of chromium (VI) with unloaded or tricaprylylamine loaded foams, TBP-amine-loaded foams and TBP loaded foams, respectively.

Iodometric microdetermination of thallium in aqueous media and in organic compounds by chemical amplification reactions

La methode peut etre appliquee au dosage de solutions contenant Tl(I) ou un melange de Tl(I) et Tl(III)

Detection and semiquantitative determination of nickel with dimethylglyoxime-loaded foam.

Rapid, sensitive and selective detection and semiquantitative determination of nickel in aqueous solution can be obtained by using dimethylglyoxime loaded on polyurethane foam, either by batch or column extractions, the detection limits being 0.05 and 0.01 ppm respectively.