Atomic Absorption Spectrophotometric Determination of Chelated Iron in Iron Chelate Concentrates: Collaborative Study

Abstract

An atomic absorption Spectrophotometric (AAS) method for determining chelated iron in iron chelate concentrates was collaboratively studied by 13 laboratories. Nonchelated iron was selectively precipitated as ferric hydroxide from an aqueous solution of the sample by adjusting to pH 8.5 with sodium hydroxide. A filtered portion of the sample solution was diluted with 0.5N HC1, and the iron was determined by AAS using standards containing disodium EDTA. Six pairs of iron chelate materials (12 samples) were analyzed and the average coefficients of variation were iron EDTA 3.52%, iron HEDTA 4.16%, iron DTPA 3.55%, iron EDDHA 3.52%, iron citrate 2.86%, and iron DPS 8.47%. The method has been adopted official first action.

Organic elemental analysis

“…Brossier et al (39) determined iron in ferrocene and its derivatives by flameless atomic absorption spectrometry. A collaborative study of the determination of iron in chelates by atomic absorption spectrometry has been published (40). Farroha et al (41) determined milligram amounts of organolead in petroleum by digestion with HN03-H202-HC104 and titration with 0.2 mM Na2Mo04 using a Pb2+ selective electrode.…”