Thermal treatment of plasma-synthesized goethite improves Fenton-like degradation of orange II dye

Autor: Serge Nzali, Antoine Tiya-Djowe, Samuel Laminsi, Eric M. Gaigneaux, Estella Tamungang Njoyim
Rok vydání: 2016
Předmět:
Zdroj: Environmental Chemistry Letters. 14:515-519
ISSN: 1610-3661
1610-3653
Popis: Various iron oxides are used for Fenton reactions to degrade organic pollutants. The degradation efficiency may be improved by transforming an iron oxide phase to another. Here, we report on the transformation of goethite into hematite by thermal treatment at 400 °C. The products were analyzed by X-ray diffractometry, Raman spectroscopy, scanning electron microscopy and N2-physisorption. The catalytic activities were measured for orange II bleaching at initial concentration of 25 mg L−1, pH 3, catalyst concentration of 0.2 g L−1; 5 mM H2O2, 30 °C. Results show that the synthesized goethite was successfully transformed into hematite, and the specific surface area of the material increased from 134 to 163 m2 g−1. The bleaching efficiency of the orange II dye reached 100 % for the hematite product, versus 78 % for goethite. Therefore, a moderate thermal treatment of a plasma-synthesized goethite improves the catalytic oxidation of organic pollutants.
Databáze: OpenAIRE