초록
<P><B>Abstract</B></P> <P>Lignocellulosic biomass is a promising feedstock for ethanol production, but lignin, a polyphenol, hampers the use of enzymes for its saccharification; pretreatment is thus key to preparing such feedstock. Ozonation was previously demonstrated as an effective pretreatment, but claimed to be uneconomical due to the assumed need for lignin mineralization. We analyzed, for the first time, ozonation of highly concentrated tannic acid (TA) solution (60g/L) as a lignin model. Most of the TA disappeared within 3.5h, following triple-phase kinetics with two transition points: at 7min and 60min of ozonation for 0.4L ozone reactor. Maximal enzymatic activity was found at the first transition point, demonstrating that very short ozonation that results in partial decomposition of TA, is enough to remediate TA’s negative effect on cellulase activity. Short ozonation could decrease energy input by up to 97%, making ethanol production more economically competitive.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ozonation process was applied to high concentration of tannic acid (60g/L). </LI> <LI> Triple-phase, first-order kinetics was observed with two transition points. </LI> <LI> Maximal cellulase activity found at low TOD and first transition point. </LI> <LI> Reduction of 97% in energy input for pretreatment is suggested. </LI> <LI> Full mineralization is not necessary for efficient conversion of biomass to ethanol. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>