Sensitive Differential Pulse Polarographic Determination of Molybdenum Using The New Catalytic System Mo(VI)‐Phenantroline‐Chlorate

Abstract

It was found that in acidic chloride media the complex of Mo(VI) with 1,10-phenantroline induces catalytic reduction of KClO 3 . This catalytic effect can be utilized for sensitive differential pulse polarographic determination of Mo(VI) with a low detection limit of 2.9 Â 10 À11 M (2.8 ng/L). The optimal Mo(VI) response was obtained at pH 2.8, in the presence of (6 -12) Â 10 À5 M 1,10-phenantroline and 2 Â 10 À2 M KClO 3 . The sensitivity was 1.73 nA/nM and the catalytic response was linear up to 7.5 Â 10 À7 M Mo (VI). The interferences from inorganic ions and surface-active substances were investigated. The results of the determination of Mo(VI) in CRM water sample showed good reproducibility (R.S.D. for standard solution is below 1.2% and for water samples is 8.9%) and accuracy of the elaborated catalytic polarographic method.