Dephenolization and discoloration of olive mill wastewater using coagulation, filtration, and hydrogen peroxide oxidation (Nov, 10.1007/s13762-022-04578-x, 2022)

Olive industries include processes of production produce liquid wastes and solid contaminates. The solid part produced is manned olive stone waste, while the major product liquid part is olive mill wastewater (OMW), which has many contaminants in the water and solid parts. More than 95% of the olive production and its processes are in the Mediterranean countries. As a result, OMW is considered a toxic source that is harming the environment and water bodies. There are many methods for disposing of OMW in the environment to avoid toxicity. Different basic methods of discharging OMW include evaporation, landfilling, circulating pond, and crop irrigation. This research introduces a treatment process by adding low-cost chemical coagulants, filtration processes, and finally, treatment by adding hydrogen peroxide (H2O2). The samples were analyzed in two places: Al-Hussein Bin Talal University (AHU) laboratories and Royal Scientific Society (RSS) laboratories. Results show the effectiveness of ferric chloride (FeCl3) and ferric oxide (Fe2O3; inorganic chemical coagulants) with lime (Ca (OH)2) plus filtration process followed by adding the H2O2. The overall removals in percentage reached 99.5%. This approved those inorganic chemical coagulants used helped through suspended, colloidal, and dissolved matter removal, destabilized by adding the chemical coagulants FeCl3 and Fe2O3. © 2022, The Author(s) under exclusive licence to Iranian Society of Environmentalists (IRSEN) and Science and Research Branch, Islamic Azad University.