Resumo

DOMINGUEZ-MALDONADO, J.A. et al. Reduction of cation exchange capacity in a microbial fuel cell and its relation to the power density. Rev. Mex. Ing. Quím [online]. 2014, vol.13, n.2, pp.527-538. ISSN 1665-2738.

A PEM type Microbial Fuel Cell was designed and constructed. This cell consisted of four pairs of chambers with a volume of 0.5 L each one of them, separated by a Nafion®117 membrane. The cell was monitored during 122 days, using synthetic wastewater as carbon source. The reduction of cation exchange capacity in the membrane was evaluated in two phases: 1 and 2, the first one at 43 days and the second one at 79 days. The cationic exchange coefficients obtained were 2.03 ×10^-3 and 1.25 ×10^-3 meq g^-1 polymer, for phase 1 and 2 respectively, indicating a decrease in the cation exchange properties in the membrane. The maximum obtained power densities were 325 and 97 mW.m^-3, respectively. The reduction of power density at phase 2 was attributed to a decrease in the cation-exchange capacity by iron fouling and a formation of a biofouling layer in the membrane.

Palavras-chave : cation exchange capacity; proton exchange membrane; biofouling; microbial fuel cell; power density.