RuO<sub>2</sub>-Ti Electrode-Assisted Electro-Biodegradation for Enhanced Rhodamine B Elimination.

Abstract

Electro-oxidation (EO) is a rapid and effective method for the elimination of organic and inorganic pollutants from wastewater. In this study, the titanium-based mesh electrodes Ti/TiO₂-RuO₂ were used for the removal of rhodamine B (RhB) azo dye in simulated water by the treated EO and EO-treated biodegradation (EO and BD) with 20 mA/cm^-2 direct current applied for the EO system, and the color removal was measured by UV-spectrophotometer. The chemical oxygen demand (COD) was greatly reduced to 78% in the EO-treated and 93% in the EO-treated biodegradation sample, respectively, and the decolorization was accomplished in 30 min in 10 ppm. The biodegradation data verify that the bacterial strain used both organic and inorganic materials. TOC (total organic carbon) in EO and EO with biodegradation were 57.2% and 86.7%, respectively. It confirms that the EO with biodegradation effectively removes RhB and aids in complete mineralization. Fourier transform infrared spectroscopy (FTIR) confirms the functional groups cleaved during the process HRMS concluded that the intermediate products NH, C-N, and C=O were generated during EO with biodegradation. The calculated toxicity of LC50 and EC50 values of RhB was observed in RhB 6 (100<) in water for fish, daphnid, and green algae. The toxicity study confirms that the majority of intermediates from EO and BD were scarcely harmful. Overall, this study concludes that RhB was effectively degraded by the EO and mineralized by the BD, and this combined treatment plays a vital role in the remediation of pollutants in the wastewater effluent treatment plant.