高氯酸氧化三价锰滴定法测定硅锰铝合金中的锰

Determination of Manganese Content in Silicon-manganese-aluminum Alloy by Perchloric-acid-oxidation-trivalent-manganese Titrimetric Method

利用锰的价态变化原理,以硝酸、氢氟酸、磷酸溶解试样,在大量磷酸存在的情况下,用高氯酸在200℃左右时,将二价锰氧化为三价锰,以N—苯代邻氨基苯甲酸为指示剂,用硫酸亚铁铵标准溶液滴定三价锰,借此测定锰含量,测定结果表明,相对标准偏差小于0.105%,完全能满足硅锰铝合金中锰测定准确的需要。

Adopting the principle of valent state change of manganese, the samples are dissolved by nitric acid, hydrofluoric acid and phosphoric acid. In the presence of a large quantity of phosphoric acid, at about 200℃, perehlorie acid is used to oxidize bivalent manganese into trivalent manganese, with N-phenylated anthranilie acid as a tracer agent, the standard solution of ammonium ferrous sulphate is used to titrate trivalent manganese, hy which the content of manganese is determined, showing a satisfactory result, with a relative standard deviation less than 0.105%, thus fully meeting the requirement in accuracy.