Indirect complexometric determination of zinc(II) in ores, alloys and complexes using 1,10-phenanthroline as selective masking agent

Abstract

An indirect complexometric method is described for the determination of zinc(II), 1,10-phenanthroline being used as masking agent. Zinc(II) in a given sample solution is initially complexed with an excess of EDTA and the surplus EDTA is titrated with lead nitrate solution at pH 5.0–6.0 (hexamine), using xylenol orange as indicator. An excess of 1,10-phenanthroline is then added, the mixture shaken well and the EDTA released from the Zn–EDTA complex is titrated with a standard lead nitrate solution. Results are obtained for 2–32 mg of Zn with relative errors ⩽0.6% and standard deviations ±0.06 mg. The interferences of various ions are studied. The method is applied for the determination of zinc in its alloys, ores and complexes.