高含量铜、钴、钼精矿试样中铁的分析测定

Determination of Iron in Comcentrate Samples Containing High Contents of Copper,Cobalt and Molybdenum

试样经硝酸-氯酸钾饱和溶液分解,于盐酸溶液中,用氢氧化铵—氯化铵沉淀分离。在强盐酸溶液中用二氯化锡溶液还原铁的三价离子,过量的二氯化锡用碘酸钾、硫酸银氧化还原,以二苯胺磺酸钠为指示剂,用重铬酸钾标准溶液滴定。

The sample is decomposed by the saturated solution of nitric acid - potassium（HNO3 - KClO3）, then is precipitated in hydrochloric acid（HC1）solution using the ammonium hydroxide-ammonium chloride （NIL, OH-NH4Cl） solution and separated out. In Strong hydrachloric acid solution, the trivalent iron ions （Fe3~ ）are reducedby tin dichloride solution,overplus Sncl2 is Oxidized and reduced using patassium iodate（KlO3） and sulfate ion （SO4^2- ）, then is tityated by the standard solution of potassium dichromate （K2Cr2O7） using dianiline as an indicator