Authors: Liping Huang Bruce E Logan
Publish Date: 2008/07/15
Volume: 80, Issue: 4, Pages: 655-
Abstract
A mediumscale 077 l aircathode brushanode microbial fuel cell MFC operated in fedbatch mode using xylose 20 mM generated a maximum power density of 13 ± 1 W/m3 673 ± 43 mW/m2 Xylose was rapidly removed 835 within 8 h of a 60h cycle with 421 of electrons in intermediates 85 ± 02 mM acetate 59 ± 001 mM ethanol 43 ± 01 mM formate and 13 ± 003 mM propionate 91 captured as electricity 161 in the remaining xylose and 327 lost to cell storage biomass and other processes The final Coulombic efficiency was 50 At a higher initial xylose concentration 54 mM xylose was again rapidly removed 869 within 24 h of a 116h cycle intermediates increased in concentration 184 ± 04 mM acetate 78 ± 04 mM ethanol and 21 ± 02 mM propionate but power was lower 52 ± 04 W/m3 Power was increased by operating the reactor in continuous flow mode at a hydraulic retention time of 20 h 20 ± 1 W/m3 with 66 ± 1 chemical oxygen demand removal These results demonstrate that electricity generation is sustained over a cycle primarily by stored substrate and intermediates formed by fermentation and that the intermediates produced vary with xylose loadingThe authors would like to acknowledge David Jones and Elodie Lalaurette for sample analysis assistance This research was supported by SRF for ROCS SEM of China Key Laboratory of Industrial Ecology and Environmental Engineering Ministry of China Education the National Renewable Energy Laboratory and the Paul L Busch Award administered by the Water Environment Research Foundation
Keywords: