ISO 9647-2020 pdf download.Steel – Determination of vanadium content一Flame atomic absorption spectrometric method (FAAS).
5 Reagents
During the analysis, unless otherwise specified, use only reagents of recognized analytical grade and only grade 2 water as specified in ISO 3696.
5.1 Pure iron, containing <0,000 5% of vanadium or of low and known vanadium content. 5.2 Hydrochloric acid, p approximately 1,19 g/ml. 5.3 Nitric acid, p approximately 1.40 g/ml. 5.4 Perchloric acid, p approximately 1,67 g/ml. WARNING — Perchloric acid vapour can cause explosions in the presence of ammonia, nitrous fumes or organic material In general. 5.5 Hydrochloric acid solution, 1 + 50. Add 10 ml of hydrochloric acid (5.2) to 500 ml of water and mix. 5.6 Aluminium solution, 20 g/l. Dissolve 90 g of aluminium chloride hexahydrate (A1C136H2O) in about 300 ml of water, add 5 ml of hydrochloric acid (52). dilute to 500 ml with water and mix. 5.7 Vanadium standard solutIon, 2,0 g/l. 5.7.1 Preparation using vanadium metal Weigh (1,000 ± 0,001) g of vanadium (V  99,9%) and transfer it into a 400 ml beaker. Add 30 ml of a mixture of three volumes of hydrochloric acid (52) and one volume of nitric acid (53). Cover with a watch glass and if necessary. heat gently to assist dissolution. When dissolution is complete evaporate the solution to just before dryness and add 20 ml of hydrochloric acid (5.2). Allow to cool to room temperature and transfer the solution quantitatively into a 500 ml one-mark volumetric flask. Dilute to the mark with water and mix. 1 ml of this solution contains 2,0 mg of vanadium. 5.7.2 PreparatIon using ammonlum metavanadate Dry several grams of ammonium metavanadate (NH4VO3) (purity >99,9 %) in an oven at 100 °C to 105 °C for at least one hour and allow to cool to room temperature in a desiccator.
NOTE A drying temperature over 110 °C will cause decomposition of ammonium metavanadate. Keep strictly to the drying temperature specified.
Weight 2,296 g of the dried product into a 600 ml beaker, add about 400 ml of hot water and gently simmer to dissolve.
Allow to cool, transfer the solution quantitatively into a 500 ml one-mark volumetric flask. Dilute to the mark with water and mix.
I ml of this solution contains 2.0 mg of vanadium.ISO 9647 pdf download.