Treatment of industrial wastewater containing highly resistant organic compounds with combined catalytic oxidation

The wastewater from the pharmaceutical industry, containing various chemicals and active pharmaceutical ingredients, can have toxic effects on the ecosystem if discharged without treatment. To mitigate this effect, it is essential to treat pharmaceutical industry wastewater, which contains highly resistant organic compounds, using effective methods that do not generate harmful by-products. In this study, electro-Fenton, photo electro-Fenton, electrocatalytic, and photo electrocatalytic oxidation processes were employed for wastewater treatment. In the electrocatalytic and photo electrocatalytic oxidation processes, electrodes coated with TiO₂, Ag/TiO₂, and Zn/TiO₂ were used to investigate the effect of different catalysts on catalytic oxidation efficiency. The study concluded that Ag-doped TiO₂ was found to be suitable in terms of treatment efficiency and toxicity for the treatment of pharmaceutical industry wastewater in the photo electrooxidation process. Using Ag/TiO₂ electrodes as anode and cathode, along with a 40W UVA lamp, the photo electrocatalytic oxidation process achieved COD, color, and UV254 removal efficiencies of 76.80%, 84.74%, and 86.03%, respectively. Additionally, the LD50 value of the raw wastewater, initially 20%, increased to 100%. The study observed that the doping of TiO₂ enhanced the treatment efficiency.