Résumé
In this study we demonstrate the efficiency of a natural mineral as a photocalyst. This natural mineral was provided from the iron ore deposit from Chaabet-El-Ballout which is located in North-East of Algeria. The characterization analysis of the mineral by the Energy-dispersive X-ray spectroscopy (EDX) revealed that the natural powder has a mixed elemental composition and consist mainly of iron oxide with 50 % of iron. In order to determine the crystal phase composition of the natural iron oxide (NIO), X-ray diffraction (DRX) measurement and infrared absorption spectroscopy (FTIR) were carried out. The results showed that the NIO has a mixed crystal structure composed mainly of hematite and lesser extent of goethite. The specific surface area and the total pore volume of the NIO were 79.015 m
and 0.0892 cm
respectively, measured by the Brunauer Emmett–Teller method (BET). The Raman spectrum of the NIO confirmed that the sample has seven characteristic peaks attributable to hematite. The optical properties of soil powder were examined by UV-vis diffuse reflectance spectroscopy (DRS). The pH of point of zero charge (pH
) of the adsorbent was determined, a value of 8.3 was found. The photocatalytic activity of the NIO particles was tested by the decomposition of aqueous solution of different class of compounds; phenolic compounds, pesticides and dyes due to their presence in many types of wastewaters. The sorption on the surface of the NIO with photocatalytic oxidation using oxalic acid and hydrogen peroxide would be an effective oxidation process for the removal of contaminants under UV and solar irradiation. High percentages of degradation of 1- Naphtol (1-NP) and Linuron were found about, 94.6 %, 97.2 % respectively, in presence of NIO and H
under UV irradiation. The presence of oxalic acid with NIO enhanced the photodegradation of 2,6-dimethylphenol (2,6-DMP), 2-chlorophenol (2-CP) and Methylene blue (MB) with 72 %, 92 % and 100 % percentages of degradation respectively.