Search Results (2)

The presence of acetaminophen (ACTP) in aquatic environments has become a significant concern due to its environmental persistence and the potential formation of toxic transformation products. This study systematically compares the performance of three electrochemical advanced oxidation processes (EAOPs), electro-oxidation (EO), electro-Fenton (EF), and solar photo-electro-Fenton (SPEF), for the degradation and mineralization of ACTP in aqueous media using boron-doped diamond (BDD) electrodes. Reactions were conducted under varying operational parameters, including current densities (15–60 mA cm⁻²), initial ACTP concentrations (10–30 mg L⁻¹), and Fe²⁺ dosages. In the SPEF system, natural sunlight was utilized as the source of UV-A irradiation (30–35 W m⁻²). Among the evaluated processes, SPEF exhibited the highest degradation efficiency, achieving up to 97% ACTP removal and 78% chemical oxygen demand (COD) reduction within 90 min. High-performance liquid chromatography (HPLC) analysis identified phenol and catechol as major intermediates, suggesting a degradation pathway involving hydroxylation, aromatic ring cleavage, and subsequent oxidation into low-molecular-weight carboxylic acids. Kinetic modeling revealed pseudo-first-order behavior, with a maximum rate constant of 0.0865 min⁻¹ under optimized conditions determined via Box–Behnken experimental design. Additionally, SPEF demonstrated enhanced energy efficiency (~0.052 kWh gCOD⁻¹) and improved oxidant regeneration under solar radiation, highlighting its potential as an environmentally friendly and cost-effective alternative for pharmaceutical wastewater treatment. These results support the implementation of SPEF as a sustainable strategy for mitigating the environmental impact of emerging contaminants, especially in regions with high solar availability and limited technological resources. Full article

Dairy wastewater (DW) contains a high concentration of organic and inorganic pollutants. In recent years, extensive research has been conducted to develop more efficient techniques for the treatment of DW. Electrochemical advanced oxidation processes (EAOPs) have gained significant attention among the various treatment approaches. EAOPs rely on electrochemical generation of hydroxyl radicals (•OH) which are considered highly potent oxidizing compounds for the degradation of pollutants in DW. In this paper, we provide an overview of the treatment of DW using various EAOPs, including anodic oxidation (AO), electro-Fenton (EF), photo electro-Fenton (PEF), and solar photo electro-Fenton (SPEF) processes, both individually and in combination with other techniques. Additionally, we discuss the reactor design and operating parameters employed in EAOPs. The variation in degradation efficiency is due to different oxidizing agents produced in specific approaches and their pollutant degradation abilities. In AO process, •OH radicals generated on electrode surfaces are influenced by electrode material and current density, while EF procedures use Fe²⁺ to create oxidizing agents both on electrodes and in the DW solution, with degradation mechanisms being affected by Fe²⁺, pH, and current density; additionally, PEF and SPEF approaches enhance oxidizing component production and pollutant degradation using ultraviolet (UV) light. Integration of EAOPs with other biological processes can enhance the pollutant removal efficiency of the treatment system. There is a scope of further research to exhibit the effectiveness of EAOPs for DW treatment in large scale implementation. Full article