<b>Polypropylene based anion exchange fiber for enrichment and determination of trace indium by GFAAS</b>

Abstract

Indium was enriched and separated by a new polypropylene based anion exchange fiber before determined by graphite furnace atomic absorption spectrometry (GFAAS). Indium can be enriched quantitatively by 0.1 g of fiber at the flow rate within 6 mL·min^-1 in the pH 4 and can be desorbed quantitatively with 10 mL of 1.0 M nitric acid from the fiber column. The fibers were soaked in 2 M sodium hydroxide sodium hydroxide solution for activation and were washed with distilled water at least thirty times until neutral for regeneration, The saturated capacity of the fiber for In(III) was 1.32 mg·g^-1. The activation energy (E_a) of the fiber adsorption In(III) was 89.3 kJ·mol^-1. The method was used to enrich trace In(III) in artificial samples solution and zinc concentrate solution before determination. The method detection limit was 0.08 ng·mL^-1, the recoveries were 96.8-101%, and the relative standard deviations (RSD) were 0.1-2.1%.

 KEY WORDS: Anion exchange fiber, Separation, Enrichment, Indium, GFAAS

Bull. Chem. Soc. Ethiop. 2011, 25(2), 295-298.