Effect of hydrofluoric acid on acid decomposition mixtures for determining iron and other metallic elements in green vegetables.

Abstract

The efficiency of acid mixtures, HNO³ - HCIO⁴ -HF, HNO³ - HCI - HF, HNO³ - HCIO⁴ and HNO³ - HCl in the decomposition of four edible green vegetables, Gboma (Solanum macrocarpon), Aleefu (Amaranttius hibirid-us), Shoeley (Hibiscus sabdariffa) and Ademe (Corchorus olitorius), for flame Atomic Absorption Spectromet-er analysis of Fe, Mn, Mg, Cu, Zn and Ca was studied. The concentrations of Fe were higher (120.61 – 710.10 mg/kg), while the values of Cu were lower (2.31 – 4.84 mg/kg) in all the samples. The values of concentration for Fe were more reproducible when HF was included in the decomposition mixtures. There were no significant differences in the concentrations of the other elements when HF was included in the acid mixture as compared to the acid mixtures without HF. Therefore, the inclusion of HF in the acid decomposition mixtures would ensure total and precise estimation of Fe in plant materials, but not critical for analysis of Mn, Mg, Cu, Zn and Ca. Performance of the decomposition procedures was verified by applying the methods to analyse Standard Reference Material IAEA-V-10 Hay Powder.

Journal of Applied Science and Technology Vol. 12 (1&2) 2007: pp. 84-87