Description:
Hydrothermal conversion in subcritical
water is a conversion technique which is attractive method because of its
ability to transform wet biomass into valuable chemicals without drying. In
this study, the hydrothermal conversion of xylose was carried out in
subcritical water in the absence and in the presence of catalysts. Experiments
were performed at temperatures of 250, 300 and 350°C with a reaction time of 1
h.  Deep eutectic solvents (DES) were
used as catalysts in the hydrothermal conversion of xylose. The effects of
temperature and catalyst addition on the yields of gas and liquid products also
on gas and liquid composition were examined. DES 1 consisting of potassium
carbonate and ethylene glycol, DES 2 composing choline chloride and urea showed
catalytic activity by increasing the liquid yield. The main components were
identified as hydroxyacetic acid (glycolic acid), lactic acid, 5-hydroxy methyl
furfural, furfural and formic acid. The gas product yield was increased by
increasing temperature for all samples. The presence of DESs showed catalytic
activity on gas yield and the maximum gas yield was obtained as 31.7 % for DES2