Spectrophotometric determination of molybdenum in steel samples utilizing selective sorbent extraction on Amberlite XAD-8 resin

A preconcentration procedure, using a short column filled with Amberlite XAD-8, is proposed for the Spectrophotometric determination of traces of molybdenum. Molybdenum as a Mo(V)- thyiocyanate complex is sorbed strongly on the resin and is easily eluted with acetone. The molybdenum complex in the effluent can be determined spectrophotometrically at 462.0 nm. The influence of several ions, as interferents, was discussed. The procedure was applied to the determination of molybdenum in steel with satisfactory results (recovery ≥ 95%; relative error ≤ 3%; relative standard deviation ≤ 5% in the concentration range of 0.006–0.024%; IUPAC detection limit, 60 μg l−1 in solution).