Utilization Of Straw Lignocelluloses

The countries all over the world have paid much universal attention to the comprehensive utilization of crop straw, which mainly focus on energy, paper making, feedstuff and fertilizer. Compared with developed countries, development and utilization in this field have been going on in china, but the straw has not been used widely.This paper studied the utilization of straw lignocelluloses and the whole research was divided into two parts. One was that the cotton stalk was used for pulp and paper, the other was the use of lignocelluloses for the pretreatment process of fuel ethanol. The main results are as follows:1. The main chemical composition and the FTIR pattern of cotton stalk were tested, and the results showed that conjugate carbonyl was the main structure which led to the problem of high amount of chromophoric groups and dark color in formed slurry process.2. The medical solution with hydroxyl radical was used for alkali cooking process. The results showed that:with the liquid ratio of3:1, temperature of100℃and the holding time of90min, the brightness of raw pulp reached22.52%ISO, which improved by11.885%ISO. The coarse pulp rate reached60.16%, which improved by36.29%. The usage of low liquid ratio result to black liquor displacement per ton of pulp decrease by40%compared with conventional process.3. The affects of TAED and electromagnetic wave to the bleaching process by H2O2was studied. The replacement of conventional chlorine bleaching by H2O2bleaching could reduce secondary pollution. The results showed that when the concentration of H2O2was3%, MgSO440.05%, Na2SiO43%, TAED10%, through treatment by electromagnetic wave reactor for2min, the whiteness of unbleached pulp could reach to51.50%ISO.The reseach were also carried out about pretreatment process of preparation of fuel ethanol by straw wood cellulose. Conventional methods can’t destroy cellulose crystal structure and removal a large number of lignin, or had some effects but bring the problem of environmental pollution in follow-up production. The experiments combined physical method with chemical method to study the pretreatment process of preparation of fuel ethanol by straw wood cellulose, the results showed that:with solution which contained hydroxyl radical reactive oxygen species as additives, and when the liquid ratio was3:1, reaction time was3min, temperature was90℃, the yield of cellulose was85.98%, the removal rate of lignin reached to80.72%, crystallinity decreased by26.80%, the yield of reducing sugar was60.8%.