Strengthened pollutants abatement in wastewater through electrocoagulation and zeolite adsorption: analytical and...

As the global population rapidly increases, so does the water demand, making effective wastewater treatment essential to mitigate pollutants, including heavy metals, organic compounds, and microbial contaminants. These pollutants pose significant health risks, exacerbate environmental crises, and disrupt ecosystems, emphasizing the urgent need for sustainable solutions. This study explores the electrocoagulation-adsorption (EC-Ads) integrated treatment process as a promising approach for contaminant removal from wastewater. The method simultaneously generates in situ coagulants while leveraging the retention capabilities of zeolite. A NaOH-prefusion-mediated hydrothermal synthesis was employed to convert clay-rich illite and fumed silica by-product into pure analcime-C zeolite. This material demonstrated high crystallinity (89%), a specific surface area of 23.76 m²/g, and a cation exchange capacity (CEC) of 510 meq/100g. Initially, the EC process was optimized for chromium (VI) removal from synthetic solutions, achieving an 85% removal efficiency at an energy consumption of 0.5 kWh/g under optimal conditions (initial pH 5, current density 10 mA/cm², and electrolysis time 40 min). Subsequently, the EC and EC-Ads processes were applied to real wastewater samples. Under optimized conditions, the EC-Ads process achieved 97.85% chromium removal with an energy consumption of 7.32 Wh/L. Additionally, reductions in chemical oxygen demand (COD) and total organic carbon (TOC) were observed at 60.19% and 94.09%, respectively. Notably, complete eradication (100%) of microbial contaminants, including microflora, fungi, and coliforms, was achieved. These findings highlight the efficiency and sustainability of the EC-Ads integrated approach in removing diverse pollutants from wastewater, offering a reliable solution to enhance water quality in treatment facilities.