Desenvolvimento de célula a combustível microbiana para tratamento de efluente industrial

Abstract

Accelerated industrial development demands the search for efficient remediation technologies. Microbial Fuel Cells have the capacity to remediate organic matter rich effluent by utilizing bacteria as biocatalysts capable of oxidizing organic material while simultaneously producing electricity. In this work, the efficiency of three different anodes was investigated while utilizing dual chamber MFCs for the remediation of paper recycling plant effluent. Graphite (GR), used as a control, underwent an acid purification treatment to ensure a contaminant-free interface. The 3D-CB electrode was developed via stereolithographic printing with a gyroid geometry, subsequently subjected to successive immersion baths and ultrasonication in a mixture of carbon black and PTFE, aiming to coat the internal passages and create a conductive surface. Finally, the INPCB-Resin anode consisted of a laboratory-formulated resin based on specific monomers and porogenic agents, doped with iron nanoparticles and carbon black. This material was molded, photopolymerized under UV light, and subjected to a two-stage carbonization process: an initial phase in an oxidizing atmosphere and a final stage in an inert nitrogen atmosphere for structural conversion, resulting in an electrode with enhanced conductivity and electrocatalytic properties.The paper effluent containing chemical oxygen demand 5030 mg/L was used as feedstock in the MFCs. GR-anode (914.1 mA/m2; 320.8 mW/m2) and 3D-CB-anode (882.8 mA/m2; 299.3 mW/m2) both achieved 56% COD removal, while INPCB-anode (5709.2 mA/m2; 3754.9 mW/m2) was the best performing, with over 80% COD removal. Photopolymerized doped anode exhibited superior performance in terms of both organic matter oxidation and conductivity, indicating higher effectivity of this type of electrode in MFC technology.