Thiocyanate method evaluation

In a method described by Kiriyama and Kuroda [500], molybdenum is sorbed strongly on Amberlite CG 400 (Cl form) at pH 3 from seawater containing ascorbic acid, and is easily eluted with 6 M nitric acid. Molybdenum in the effluent can be determined spectrophotometrically with potassium thiocyanate and stannous chloride. The combined method allows selective and sensitive determination of traces of molybdenum in seawater. The precision of the method is 2% at a molybdenum level of 10 xg/l. To evaluate the feasibility of this method, Kiriyama and Kuroda [500] spiked a known amount of molybdenum and analysed it by this procedure. The recoveries for 4 to 8 xg molybdenum added to 500 or 1000 ml samples were between 90 and 100%. 

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