%0 Journal Article
%T Impact of Furfural on Rapid Ethanol Production Using a Membrane Bioreactor
%A P£¿ivi Ylitervo
%A Carl Johan Franz¨¦n
%A Mohammad J. Taherzadeh
%J Energies
%D 2013
%I MDPI AG
%R 10.3390/en6031604
%X A membrane bioreactor was developed to counteract the inhibition effect of furfural in ethanol production. Furfural, a major inhibitor in lignocellulosic hydrolyzates, is a highly toxic substance which is formed from pentose sugars released during the acidic degradation of lignocellulosic materials. Continuous cultivations with complete cell retention were performed at a high dilution rate of 0.5 h £¿1. Furfural was added directly into the bioreactor by pulse injection or by addition into the feed medium to obtain furfural concentrations ranging from 0.1 to 21.8 g L £¿1. At all pulse injections of furfural, the yeast was able to convert the furfural very rapidly by in situ detoxification. When injecting 21.8£¿g L £¿1 furfural to the cultivation, the yeast converted it by a specific conversion rate of 0.35 g g £¿1 h £¿1. At high cell density, Saccharomyces cerevisiae could tolerate very high furfural levels without major changes in the ethanol production. During the continuous cultures when up to 17.0 g L £¿1 furfural was added to the inlet medium, the yeast successfully produced ethanol, whereas an increase of furfural to 18.6 and 20.6 g L £¿1 resulted in a rapidly decreasing ethanol production and accumulation of sugars in the permeate. This study show that continuous ethanol fermentations by total cell retention in a membrane bioreactor has a high furfural tolerance and can conduct rapid in situ detoxification of medium containing high furfural concentrations.
%K ethanol
%K Saccharomyces cerevisiae
%K membrane bioreactor
%K cross-flow filtration
%K furfural conversion kinetics
%U http://www.mdpi.com/1996-1073/6/3/1604