Employing the Cost-effective Composite Cathodes for Bio-Fenton facilitated degradation of Acid Red 114 integrated into Hydrogen Peroxide Synthesizing Microbial Fuel Cell

Abstract

The foremost obstacle in scale up application of Bioelectro-Fenton dye wastewater treatment process is high cost of cathode material. The study proposes a low-cost activated carbon/stainless steel (AC/SS) and Graphite powder/stainless steel (GP/SS) composite cathodes, where SS allocates the current, while AC/GP concurrently supports Hydrogen peroxide (H2O2) production. Composite AC/SS and GP/SS cathode enabled Acid Red 114 (AR 114) oxidative removal by means of bio-electro-Fenton in microbial fuel cell (MFC) is also investigated. Characterized by different microscopic, spectroscopic, and electrochemical techniques, it is observed that the composite AC/SS and GP/SS cathodes may well be fabricated and involve in H2O2 and power generation of 1420 µM /2680 µM and 4000 mWm−3/4050 mWm−3 respectively. The results also disclose that the MFC system efficiency is crucially associated to operating conditions involving initial AR 114 concentration (20 mg/L), catholyte pH (3), different catholytes, their concentration (75 mM), and Fe2+ dosage (0.5 mM). All investigated conditions are observed to impact the degradation efficiency and apparent first order rate constant for AR 114. The corresponding rate constants and efficiency for the degradation for both cathodes are 0.13 h−1/ 0.08 h−1 and 96%/90%, respectively. The outcomes validate these fabricated cathodes as sustainable substitute of expensive and complex material.