Extraction spectrophotometric determination of rhodium (III)‎ with o-methylphenyl thiourea

Abstract EN

Trivalent rhodium was determined spectrophotometrically as its 1:2 rhodium o-methylphenyl thiourea (OMPT) complex, extracted into chloroform from aqueous acetate buffer media at pH 5.4.

The complex exhibits maximum absorption at 320 nm (Molar absorptivity 9.76 · 103 L mol 1 cm1), Sandell’s sensitivity 0.0105 lg of rhodium(III) cm2.

Beer’s law obeyed up to 10.0 lg/ml.

The method is free from a large number of interferences from cations and anions.

The method is simple, selective and reproducible.

It permits separation and determination of rhodium(III) from synthetic mixtures corresponding to alloys.

A scheme for mutual separation of palladium(II), rhodium( III), platinum(IV) and iridium(III) has been developed.