可循环混合溶剂分离水稻秸秆纤维素  

Isolation of Cellulose from Rice Straw with Recyclable Mixed Solvents

作　　者：王伟[1] 姜曼[1] 朱世步[1] 周祚万[1] 

机构地区：[1]材料先进技术教育部重点实验室,西南交通大学材料科学与工程学院,四川成都610031

出　　处：《材料科学与工程学报》2011年第1期74-79,138,共7页Journal of Materials Science and Engineering

基　　金：四川省科技支撑计划资助项目(09GG1632)

摘　　要：粉碎的水稻秸秆经水煮和抽提预处理后,采用乙二醇(EG)和水的混合体系(体积比9∶1)为溶剂,在酸或碱催化作用下,分离得到纤维素,同时回收木质素和半纤维素;对所得样品的组分含量、晶体结构、微观形貌等进行了分析。结果表明:经水煮和抽提预处理后,秸秆纤维束状结构变得疏松;在0.1mol/L的硫酸催化下,经混合溶剂处理所得样品的综纤维素含量达到86.59%(其中纤维素含量为83.09%),酸不溶木质素含量为3.70%;相同条件下,以0.1mol/L氢氧化钠为催化剂,所得样品中酸不溶木质素含量为4.21%。研究还发现,混合溶剂可高效回收并循环使用。基于实验结果和结论分析,对催化剂可能的作用机理解释为:在适当浓度的酸或碱作用下,木质素的重聚合被有效抑制,从而促进了其在混合溶剂中溶解,并使其从秸秆组织中分离。It is of great importance to make full use of the biomasses such as straws with high value by environmental process.The cellulose was isolated from pulverized rice straw（RS） with mixed solvent of ethylene glycol（EG） and water in the presence of different catalysts,after pre-cooking and extracting with hot water,and the lignin and hemicelluloses were recovered in the same procedure.Structures and morphologies of the obtained samples were characterized by X-ray diffractometry（XRD）,Fourier transform infrared（FT-IR） spectroscopy and environmental scanning electron microscopy（ESEM）,the components were also analyzed.It is observed that the fibril bundles become loose after cooking and extracting with hot water.The related mixture solvent,in the presence of sulphuric acid（0.1 mol/L） as catalyst,displayed a good effect for isolating the components from the rice straw.The obtained solid samples were detected to contain 86.59% holocellulose（83.09% of which is cellulose）,and 3.70% lignin.As a comparison,the lignin could also be reduced to（4.21%） with sodium hydroxide（0.1mol/L） as catalyst in the same procedure.The recovered EG-water solvent is proved to be still efficient for resolving lignin and hemicelluloses from the rice straw.The mechanism for the function of the catalysts is suggested that the repolymerization of lignin-fragments might be inhabited in the presence of certain concentration of acid or alkali,which promotes the delignification and isolation of lignin.

关 键 词：水稻秸秆 纤维素 乙二醇-水混合溶剂 催化剂 

分 类 号：TQ352[化学工程] TQ353