Dissolution of synthetic crystalline and noncrystalline iron oxides by organic acids

摘要: Abstract Thirteen organic acids and fulvic acid were used in dissolution experiments with laboratory-synthesized noncrystalline Fe oxide, hematite goethite to determine the effect of properties on kinetics pH-dependence oxide dissolution. After 100 h reaction had completely dissolved at pH 3.5 presence oxalic, malonic, malic, citric tartaric as well EDTA, DTPA NTA. Acetic, lactic, salicylic, phthalic much less reactive. Dissolution was generally lower 5.5 than 3.5. Hematite solubilized a lesser extent oxides, presumably due surface areas differences type arrangement hydroxyl oxygen groups. Oxide solubilities predicted using formation constants Fe-organic complexes approximately measured for different material, whereas slow times limited levels far below those predicted. The observed explained basis adsorption onto variable-charge surfaces steric limitations large chelating acids.