Evaluación de grafeno y magnetita como membranas de intercambio de electrones en celdas de combustible microbianas.

Abstract

This work aims to evaluate graphene and magnetite as electron exchange membranes in Microbial Fuel Cells (MFCs) to improve voltage stability and efficiency in the generation of bioelectricity, an Andean high moor soil of Colta Canton was used as inoculum, through a system of three clusters to obtain a composite sample, in this its physical-chemical characteristics were analyzed. The substrate used a 50:50 mixture of fruits (orange: Citrus sinensis, banana: Musa acuminata L. and apple: Pyrus malus L.) and vegetables (pea: Pisum sativum L., bean: Vicia faba L., squash: Cucurbita Duchesne maximum), of which Carbon, Nitrogen, Hydrogen and Sulfur (CNHS) was analyzed; The graphene membrane was obtained by direct exfoliation of graphite oxide, previously treated in an ultrasonic bath, on a carbon fiber fabric, simultaneously the magnetite was synthesized from ferric chloride and ferrous chloride. The voltage generated by the MFCs was monitored for fifteen consecutive days, subsequently the efficiency of the materials used as membranes was estimated through a comparison of power density and CHNS degradation. The average voltage obtained by graphene cells was 131mV, its power density of 9.17mW / m2 and a substrate degradation of 8.60% (N), 35.29% (C), 24.49% (H) and 12.16% ( S), while magnetite cells achieved a degradation of 6.44% (N), 24.05% (C), 19.02% (H) and 11.35% (S), a voltage of 14mV and a power density of 0, 22 mW / m2, so with a 95% confidence level and sufficient statistical evidence the graphene membrane has a higher performance with a power density 42 times higher in relation to magnetite, for new research it is advisable to evaluate other combinations of materials which benefit the applicability of large-scale MFCs.