A comprehensive investigation of transforming recyclables into resources: electrocoagulation for sulfamethoxazole removal from hospital effluents.

Abstract

Refractory pharmaceuticals in hospital wastewater pose serious environmental and health risks. In this regard, electrocoagulation (EC) as an onsite treatment methodology has been found effective in removing toxic compounds; however, high electrode costs limit large-scale implementation. As a low-cost alternative, waste aluminium cans anode (AA_can) and waste steel mesh cathode were investigated for the removal of sulfamethoxazole (SMX) through the EC process. Detailed morphological, chemical, and electrochemical properties of the sacrificial anode (AA_can) and EC-sludge were evaluated through different characterisations. Furthermore, under optimised conditions, the process achieved 76.3 ± 2.4% removal of SMX, conforming to pseudo-first-order kinetics with a rate constant of 0.11 min⁻¹, and incurred an operational cost of INR 1.78/m³. Additionally, the EC process was found effective for the treatment of different wastewater matrices with a high reusability of 1143 times before dissolution. Moreover, the life cycle analysis shows that AA_can-based EC has sevenfold lower environmental impact than the traditional EC process. Thus, using discarded aluminium cans as sacrificial anode material in electrocoagulation offers a dual benefit of waste repurposing and cost-effective wastewater treatment with a positive impact on the environment compared to other coagulation processes.