应用计算机化的自动电位滴定仪分析了铁矿石中铁量,并采用小波变换法测定滴定终点.试样溶液中的三价铁直接用三氯化钛还原至二价,溶液中共存的二价铁和过量的三价钛在滴定中都被重铬酸钾标准溶液所氧化,但两者的等当点电位可明显地相互区别,不影响二价铁的滴定及其定量计算.用所提出的方法分析了铁矿石标准物质,测得的铁量与标准值相符.

Computerized automatic potentiometric titrator was used in the redox titration of iron in iron ores.The method of wavelet transformation was applied to the determination of end point of titration.Ferric ion in the sample solution was reduced by titanous chloride solution.Both of the ferrous ion and excess titanous ion in the solution were all oxidized by standard K2Cr2O7 solution,but their equivalent points were clearly differentiated from each other,and no interference occurs with titration and stoichiometric calculation of iron.In the analysis of a standard sample of iron ore by the proposed method,results of its iron content obtained were in consistency with the standard value.