| Confronted with crisis of energy shortage, people are looking for new energy tdower dependent on non-renewable energy instead of fossil fuel. The lignocelluloses are the best renewable energy, include forest, crops straw and the heels of subsidiary agricultural products etc, which are important in the energy flow and the circulation of materials of the natural ecosystems and it is the trend to product ethanol of lignocelluloses in the ethanol industry for future. In this paper, the main components of crops straw were separated and the processes of cellulose saccharification were optimized to provide the reference of using the renewable energy. The main conclusion followed.Firstly, compared with using sodium hypochlorite, ethanol, ammonia, and the alkalis'aqua hydro genii dioxide, the last method was the best solution for removing corncob lignin. The orthogonal experiment results show that, different importance factors influence of removal of lignin:time>aqua hydro genii dioxide concentration>sodium hydroxide concentration, and time was significant to the result by variance. And the removal of lignin is (78.08%) under the optimal process: aqua hydro genii dioxide concentration for 1.5%, sodium hydroxide concentration for 0.12 mol.L-1, time at 6 hours.Secondly, the experiment of removing lignin of maize straw, rape straw, cotton straw and wheat straw showed that, treated with sodium hydroxide concentration for 0.12 mol.L-1, for 6 hours, the radio of lignin removal from maize strawis this highest for 76.18% as the aqua hydro genii dioxide concentration for 2.0%; the rape straw removal of lignin is highest for 64.86% as the aqua hydro genii dioxide concentration for 1.0%; the cotton straw removal of lignin is highest for 70.09% as the aqua hydro genii dioxide concentration for 1.0% and the maize straw removal of lignin is highest for 72.25% as the aqua hydro genii dioxide concentration for 1.5%. The lignin was removed and the structures were expended by alkali aqua hydro genii dioxides by the SEM figures of lignocelluloses and holocellulose.Thirdly the separating process condition of cellulose and hemicellulose was studied. The orthogonal experiment result show that, different importance factors influence of cellulose concentration:temperature> sodium hydroxide concentration >time> solid-liquid ratio(g·mL-1); with the temperature at 121℃, the sodium hydroxide concentration for 2.5 mol.L-1, the solid-liquid radio for 1:90, the corn cob, rape straw, maize,wheat straw and cotton straw cellulose concentration are the highest for the time at 30 min,20 min,20 min,40 min and 30 min each, the contant of cellulose is above 90%.Fourthly, The cellulase activity of rape and cotton straw cellulose, logocelluloses of corn cob, maize straw and wheat straw were higher than 20 FPU·mL-1, which were 3-5 times of their materials, expectively. So they can be used to cellulase.Fifth, the hydrolyzing process condition of cellulose was studied for corn cobs by single factor and orthogonal experiment. The result show that different importance factors influence on cellulose concentration:temperature>time>the interact of temperature and time>acid concentrations. The maize straw cellulose and the wheat straw cellulose are the highest,98.89%,97.19%,98.46% each, with the temperature at 121℃, the sulphuric concentration for 22%, the hydrolysis rate of corncob cellulose,, as the time for 40min; The hydrolysis rate of cape cellulose are the highest(95.58%) as the time at 50min; The hydrolysis rate of cotton cellulose are the highest(96.25%) as the time at 60min. The hydrolyzate of corncob cellulose was fermented by the Rhizopus oryzae (saved in the lab) as 37℃for 80 hours. The use ratio of reducing sugar in the hydroluzate is one third of the glucose. This means the sugar in the hydroluzate can be used for producing to chemic monocase, like lactic acid etc.
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