| Abstract
| - Akaganeite (β-FeOOH) has been prepared by the hydrolysis of FeCl3 solutions. The effectsof microwave heating, pH of the solution, and addition of manganese with different valencestates have been studied for the optimization of its synthesis. The nucleation and growth ofakaganeite crystallites are accelerated by microwave heating. A low pH favors thecrystallization of akaganeite, and a high pH favors the crystallization of hematite. Additionof manganese appears to impede crystallization at low pH but improves it at high pH. Theanion exchange of Cl-akaganeite with F-, Br-, and OH- and some properties of differentanion-exchanged akaganeites has been investigated. The exchange rate and capacity dependon the nature of the anions. Anion exchange significantly changes the loss of chloride andaffects the decomposition of akaganeite upon being heated.
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