The Preparation and Characterization of γ-FeOOH Containing Cu, Ni or P

Abstract

Iron oxyhydroxides were prepared by oxidation and hydrolysis of Fe²⁺ containing solutions. The types of product were different for different solution pH : α- and γ-FeOOH at pH=6.0-7.0 ; γ-FeOOH at pH=7.0-8.0 ; γ- and δ'-FeOOH at pH=8.0-9.2 ; and δ'-FeOOH at pH=9.2-9.5. Preparation of iron oxyhydroxides from solutions with Cu²⁺, Ni²⁺ and PO₄^3- were also carried out at pH=7.5. It was found that the ion addition increased the specific surface area and decreased the crystallite size of γ-FeOOH. Adding Cu²⁺ formed α- and γ-FeOOH while γ-Fe₂O₃ was formed by Ni²⁺ and PO₄^3- addition.