Fig. 3

Mass distribution of glucan and xylan. Mass balance on glucan and xylan left in solids and solubilized in the liquid based on 100 g of initial poplar fed to pretreatment at selected temperatures and times for pretreatment with just hot water (LHW) and 0.05% sulfuric acid (EDA). Sugars could not be accurately measured for flowthrough pretreatment at 140 °C due to high volumes of water required for the long reaction times required. The “unaccounted” labels represent the inaccuracy in measurement of sugars in the pretreatment liquor. Number labels have been rounded-off to the nearest whole number for clarity