磷铁合金中磷测定方法的改进

Improvement on Methods for Determining Phosphor in Phosphorus-iron Alloy

用硝酸、氢氟酸溶解试样后，加高氯酸加热蒸发至冒浓白烟以除去硅和氟，借此将亚磷酸氧化为正磷酸，以钒钼黄光度法代替磷钼酸铵沉淀酸碱中和滴定法快速测定磷铁合金中磷含量，取得了较好效果，方法具有简便、快速、准确的优点。

Mter samples are dissolved by nitric acid and hydrofluoric acid, perchloric acid is added to heat and vaporize them until thick white smoke rises in order to remove silicon and fluorin, by which phosphorous acid is oxidized into orthophosphoric acid, then vanadium-molybdenum-yellow photometric method is used to fast determine phosphorus in phosphor-iron alloy instead of ammonium phosphor-molybdate-precipitation-acid-base-neutralization titration method, showing good results, thanks to its convenience, quickness, accuracy.