This standard specifies the use of ammonium ferrous sulfate Titrimetric method for the determination of chromium content in metallic chromium, which is applicable to metallic chromium with vanadium content not exceeding 0.20%. The determination range is chromium content ≥ 97.00%. After the sample is dissolved in dilute sulfuric acid, trivalent chromium is oxidized to hexavalent chromium by ammonium persulfate catalyzed by silver nitrate (AgNO3). Under appropriate sulfuric acid acidity, N-phenylanthranilic acid is used as an indicator and titration is carried out with ferrous sulfate ammonium standard solution. The standard also specifies the reagents and materials used, including sulfuric acid, phosphoric acid, sodium chloride, silver nitrate (AgNO3), ammonium persulfate and manganese sulfate.
| Status | Active |
|---|---|
| CCS | H11 | ICS | 77.100 |
| Release Date | 2016-08-29 00:00:00 | Implementation Date | 2017-07-01 00:00:00 |