View article

The production of aldehydes that are microbial inhibitors may occur when hexoses and pentoses in an aqueous solution are exposed to temperatures above 150 °C under acidic conditions common to acid-catalyzed lignocellulose biomass pretreatment. Concentrations greater than 0.1% of the degradation product, furfural, strongly inhibit fermentation, as was confirmed for hydrolysate that contained 0.5% (w/o) furfural. Methods of furfural removal that have been reported include sulfite or alkali addition to achieve chemical reduction, ion exchange, hydrophobic adsorption, and irreversible adsorption on activated carbon. This paper reports the removal of furfural from biomass hydrolysate by a polymeric adsorbent, XAD-4, and desorption of the furfural to regenerate the adsorbent using ethanol. Liquid chromatographic analysis showed that furfural concentrations were less than 0.01 g/L compared to the initial …