Assessing titanium vs. aluminium electrodes for wastewater remediation in the small-scale industries (SSI) textile sector

Abstract

In the pursuit of efficient and cost-effective textile wastewater treatment, this study compares the performance of titanium and aluminium electrodes in electrocoagulation (EC). Titanium electrodes, renowned for their high corrosion resistance, demonstrated superior colour removal efficiency (CRE) at 98.5 % under optimised conditions 10-minute reaction time and 18 Am⁻² current density. Conversely, aluminium electrodes, while effective, required extended reaction times and higher current densities, achieving a CRE of 97.8 %. The cost analysis favoured titanium electrodes at 2.86 ₹/m3, compared to 51.13 ₹/m3 for aluminium. For safe reuse, treated effluent subjected to activated carbon (AC) filtration, showcasing remarkable dye and metal ion removal efficiencies. The AC filtration proved exceptionally effective, as evident in the ICP-OES results. Post-EC, titanium concentration exceeded limits but was efficiently reduced to 0.001 mg/L after AC treatment, while aluminium concentration decreased significantly. Chemical oxygen demand (COD) and biological oxygen demand (BOD) removal efficiencies were compared, with titanium electrodes achieving 100 % COD and 62 % BOD removal and aluminium electrodes at 94 % COD and 47 % BOD removal. Comprehensive analytical techniques, including XPS, SEM, EDAX, FTIR, mass spectroscopy, HPLC, and ICP-OES, enhance our understanding of EC and AC mechanisms. The combined EC and AC process not only enhanced water quality but also proved environmentally sustainable, providing an eco-friendly solution for small-scale textile industries in need of efficient effluent treatment.