Abstract: Using rice hulls as raw material, the experiment utilized the method of alkali extraction after rice hulls were pretreated. Effects of alkali concentration, extraction temperature, ratio of solid to liquid and extraction time on yields of xylan were analyzed. The result showed: the content of xylan in rice hull reached 19.9%, showing a good raw material. The conditions of alkaline extraction were: pretreatment: water immersed for 3 h at 80℃; alkali concentration 10%, ratio of solid to liquid 1:10(g:mL), extraction time 3 h, extraction temperature 80℃. The yield of xylan from rice hull reached over 67.50%.

Key words: rice hull, xylan, xylo-oligosaccharide