Absorption Studies of Arsenic Using Maghemite Crystals Synthesized from Iron Waste Extracted from Ogun State Iron Mill Dumpsite

Abstract

This paper outlines the synthesis of maghemite from raw iron waste obtained in an iron mill dumpsite around Ogun state, Nigeria. Magnetite was synthesized from the ferrous precursor obtained by digesting the iron waste with concentrated H2SO4. Transformation of magnetite to maghemite was done by heating the magnetite obtained in an oven at 200˚C. To determine the absorption capacity of the synthesized maghemite sample, a stock solution of As(III) was used for the absorption. Absorption spectrum shows higher absorption of γ-Fe3O4 at higher concentration of As(III). Maximum absorption obtained is 14 mg/g. Estimated yield of γ-Fe3O4 was 32%; however a low, further study promises to improve the yield value. The study shows γ-Fe3O4 to be a good absorbent for heavy metals.