Characterization of products evolved from supercritical water gasification of xylose (principal sugar in hemicellulose)

The catalyst decomposition of xylose (the principal sugar in hemicellulose) was examined in supercritical water for temperature from 400 to 600 degrees C. Experiments were performed in the absence and presence of three main types of catalysts [alkali catalysts (K2CO3 and KOH) and metal impregnated activated carbons (Ni/AC) and (Ru/AC)] with a reaction time of 1h. Gasification yield reaches maximum values by using K2CO3 and KOH at the highest temperature of 600 degrees C. The highest H-2 yield and the highest CH4 yield were obtained by using Ru/AC and Ni/AC, respectively. Acetic acid and 5-methyl furfural were determined as the main aqueous products and reached maximum value by using Ru/AC.