Analytical Method: Cobalt in water
Reagents:
Cat.No. 173016 Spectroquant® VIS Spectrophotometer Prove 100 or
Cat.No. 173017 Spectroquant® VIS Spectrophotometer Prove 300 or
Cat.No. 173018 Spectroquant® VIS Spectrophotometer Prove 600
Cat.No. 114946 Spectroquant® Rectangular cells 10 mm
Cat.No. 100456 Nitric acid 65 % for analysis
Cat.No. 106268 Sodium acetate anhydrous for analysis
Cat.No. 116754 Water for analysis
Nitroso-R salt (CAS 525-05-3)
Method:
10-mm rectangular cell
Working instructions:
Reagent 1: Mix 11 ml of nitric acid 65 % with 90 ml of water for analysis.
Reagent 2: Dissolve 5 g of sodium acetate anhydrous in 50 ml of water for analysis.
Reagent 3: Dissolve 0.25 g of Nitroso-R salt in 100 ml of water for analysis. The reagent can be used for approx. 4 weeks when stored closed and in a dark place.
Sample pretreatment:
In a 25-ml volumetric flask mix 10 ml of sample, 0.25 ml of reagent 1, 2 ml of reagent 2, and 1 ml of reagent 3. Make up to the mark with water for analysis, close flask, and remix.
Analysis:
Call up the saved method (# 305) in the Prove photometer and perform the measurement in a 10-mm rectangular cell at 495 nm against a blank prepared with water and the reagents in the same volumes as used for the sample.
Calculation: Cobalt concentration in mg/l = Analysis result in mg/l
