Preparation and sono-Fenton performance of 4A-zeolite supported α-Fe2O3

4A-zeolite supported alpha-Fe2O3 (Fe-4A) was prepared with a hydrothermal-calcination method, and characterized by XRD. Iron oxide in the Fe-4A composite appeared in alpha-Fe2O3 phase and was highly dispersed on the surface of 4A zeolite. Fe-4A composite effectively degraded Orange II under acidic and neutral conditions via sono-Fenton process. 4A-zeolite promoted the production of cavitation bubbles under ultrasonic treatment, while alpha-Fe2O3 promoted the homolysis of oxygen molecule producing hydroxyl radical and high-valent iron-oxo species. Both actions benefited the sono-Fenton reactivity of Fe-4A. Fe-4A-4 composite with a practical alpha-Fe2O3 content of 24.9% showed the maximum sono-Fenton reactivity to Orange II. Dissolved iron ion measurement showed that Fe-4A composite represented a low iron ion dissolution-level, while the repeatability test of recycled Fe-4A showed that Fe-4A composite has high reactivity stability and a long life-time under neutral condition in the sono-Fenton reaction. (C) 2010 Elsevier B.V. All rights reserved.