Degradation of organic matter in olive-oil mill wastewater through homogeneous Fenton-like reaction

The degradation of organic matter present in olive-oil mill wastewater from two-phase olive-oil extraction process was carried out by chemical oxidation reaction. It was shown that organic matter is efficiently degraded through a Fenton-like reaction using FeCl3 as catalyst in the presence of hydrogen peroxide. Oxidation was carried out in a batch reactor with controlled temperature. Operating at pH 3.0, H2O2 concentration = 100 g dm−3, [FeCl3]/[H2O2] ratio = 0.04, and ambient temperature (281–285 K), 92.6% of chemical oxygen demand and 99.8% of total phenols were removed. Kinetics can be described by a two step first order model. The kinetic parameters at ambient temperature and pH 3 were calculated. In the temperature range 278–313 K, the best performance was obtained at 303 K. The experiments performed at different temperatures allowed to calculate the apparent activation energy Ea = 8.7 kJ mol−1.

► This work was treated the application of Fenton-like oxidation to the depuration of a real OMW. ► This problem is still an important issue to emerging needs to achieve solutions that offer new alternatives with minimum cost. ► Moreover, kinetic studies involving such wastewater were performed, which is not usually found in literature.