Spatial structure characteristic analysis of corn stover during alkali and biological co-pretreatment using XRD.

Dynamic variation in the spatial structure of corn stover during alkali and biological co-pretreatment was investigated by X-ray diffraction. The result for crystallinity and microcrystalline size of cellulose showed periodic changes during the pretreatment process. The dominant destruction periods of crystalline areas were mainly located at 3-5d and 7-17d, and prevailing destroyed amorphous areas mainly occurred at 0-2d and 5-7d. On day 7, the relative crystallinity and microcrystalline size reached 52.81% and 8.56 nm, respectively, which were the maximum and minimum values during the whole co-pretreatment. The results indicated that spatial structure change was not uniform with pretreatment time, and this was contributed to explore the vital time point of destruction during the alkali-biological pretreatment.