Evaluación del potencial energético de subproductos del beneficio del cacao para la obtención de bioelectricidad en celdas de combustión microbianas

Microbial fuel cells (MFC) are an emerging technology for the generation of bioelectricity, which also provides solutions associated with the stabilization of organic waste. Cocoa processing generates a variety of by-products, such as leachate and mucilage, which can potentially be used as a substrate in a MFC. In the present study, the performance of a double-chamber MFC prototype was evaluated, using cocoa leachate (CL), cocoa mucilage (CM) and a mixed system (CL + CM), in order to estimate the potential of these by-products to obtain bioelectricity. The MFC were operated at a concentration of 20% and 60% substrate, evaluating their performance for 10 days at room temperature. The cells were inoculated with pre-thermally treated anaerobic sludge, verifying the generation of electrical energy at intervals of one hour. Likewise, the concentration of organic matter, measured as chemical oxygen demand (COD), was determined. The highest generation of bioelectricity was evidenced in the mixed system, with values of up to 29.3 mV and a COD removal of 57.9%. It is concluded that it is possible to generate significant values of bioelectricity using cocoa by-products in a mixed system, with simultaneous removal of organic matter. The present work constitutes a contribution for the optimization of systems for the use of agro-industrial by-products as a source of renewable energy.