Hemicellulose extraction by hot pressurized water pretreatment at 160 ºC for 10 different woods: Yield and molecular weight

Abstract

A study on hemicellulose extraction from 10 different tree species was performed using a batchwise operated cascade reactor constituted by 5 units of 200mL and a buffer vessel of 2000mL where a flowrate of 150Lh−1 was fully recirculated (close loop operatioin). The experiments were performed at 160°C, 9bar and with wood chips particle size of 1.25–2mm (average solid load of 6.57g/L). The aim was to identify which wood species were the best candidates to obtain a high yield and/or molecular weight of hemicelluloses. Hydrothermal extractions at different times (from 5 to 80min) were investigated. The highest yield was obtained with eucalyptus wood (40.3wt%) after 80min of extraction. Furthermore, 3 different trends were obtained for molecular weight evolution, where the different tree species can be grouped.