| In this paper, the room temperature ionic liquids:1-butyl-3-methylimidazolium chloride was synthesized by a one-step method, and the chemical structures of it was characterized by FTIR and 13C-NMR spectroscopy.The low solubility of wood in common solvents has severely hampered the development of new methods for the efficient utilization of wood and its components. Microcrystalline cellulose,lignin and ball-milled wood flour were dissolved in this ionic liquids(BMIM]C1), by microwave heating and traditional heating. After dissolving transparent solutions of wood could be obtained when the dissolution of the lignocellulosic samples was attempted in 1-butyl-3-methylimidazolium chloride. The solubilities of the ionic liquids were studied. The research shows:10% ball-milled wood power could be dissolved in the ionic liquids by water bath at 70℃after 6 hour; the dissolution of microcrystalline cellulose could reach 25%; while for the cellulolytic enzyme lignin (CEL) could be 12.5% at the same condition. The soluble effect of microwave heating was far superior to traditional heating. Besides the dissolution temperature and time the dissolution rate of wood is highly dependent on the particle size of the wood power sample, and the water content of the ionic liquids plays a key role in determining its solubility.This thesis established a new method using ionic liquids [BMIM]C1 for extracting lignin from the milled wood flour under the condition of microwave assistant. The saturation wood solution in ionic liquids was rapidly added into an excess of organic solvent-water mixed solution and then microwave assisted extracted. The precipitated bulky material was then filtered using a G4 Buchner funnel, washed thoroughly with distilled water for many times. The lignin was filtered with ionic liquids, while, the cellulose can not through the funnel, so it can be regenerated as an amorphous mixture of its original components. By decompressing evaporation it can remove the organic solvent from the filtered-solution, then remove the ionic liquids using a stirred ultrafiltration system. We can get some solids content. Finally, a small sample of it was taken to determine its solids content. The changes of functional in ionic liquid-lignin and the cellulolytic enzyme lignin were analyzed by infrared chromatographic and measuring the phenolic hydroxyl groups. The analysis showed that the production is lignin, but some functional groups of lignin in ionic liquid-lignin were weakened or deleted after microwave irradiation. The optimum values of the five factors were obtained:choose the 60mL as the appropriate volume; 50% (V:V) acetone-water as extract solution, the appropriate tempreture was 40℃and the reaction time of it was 45min.The laccase production of Trametes hirsuta, was purified in the liquid system.In recent times, the use of room temperature ionic liquids as "green solvents" for the biocatalytic reation medium has gained considerable importance due to its negligible vapour pressure, solvating ability and easy recycling. Moreover, in some ionic liquids systems, enzymes have higher catalytic activity. Catalytic activity of laccase was decreased by adding the water-miscible ionic liquid-[BMIM]Cl. In this work we explored the effect of different concentration of organic solution and ionic liquids on laccase-catalyzed oxidations. The results indicated that:laccase is catalytically active in reaction systems containing ionic liquids or organic solution, with the mass of ionic liquid increasing, the laccase activity was decreased. The laccase activity can keep at a low condition of 10%-30% (wt%) organic solution-buffer, while 30% ionic liquids-buffer can keep the cativity 50% after 24 hours. The laccase lost activity completely when it was treated with 70% ionic liquids at once.
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