(471d) Dissolution of Cornstalk with Acetic-Based Ionic Liquids and Additives

J. L. Xu^a, F. Yu^b, X. M. Lu ^a,*, S. J.Zhang^a

^a Institute of Process Engineering, Chinese Academy Of Sciences, Beijing, 100190

^b Graduate University Of Chinese Academy Of Sciences, Beijing, 100149

^*Corresponding author: xmlu@home.ipe.ac.cn

Key words: lignocellulose, pretreatment, ionic liquids, catalyst,additives

Biomass is abundant and renewable, for example wood, cornstalk, grass and so on; as the energy crisis biomass feedstock is widely used for biofuel production, and this kind of energy production is cleaner than fossil fuels. But the production of biofuel from lignocellulose has technical challenges, particularly for the pretreatment of biomass. Cellulose, hemicellulose and lignin are main components of biomass. And these three components are connected by hydrogen bonds, including intramolecular hydrogen bond and intermolecular hydrogen-bonding. It is very hard to break the hydrogen-bonding to separate the components by pretreatment. There are many traditional pretreatment methods, for example acidolysis, alkaline hydrolysis, these methods have some shortcomings like toxicity, volatility. Ionic liquids are different salts, most of them are liquids at room temperature; and some of them have positive attributes like high thermal stability, negligible vapor pressure and non-flammability, so making ionic liquid pretreatment of biomass potentially benign to environment as compared with pretreatment by acids, alkali or other organic solvents. But the ILs used for dissolving biomass also have some shortcomings, for example high viscosity and corrosity; acetic-based ionic liquids are greener to dissolve lignocellusic biomass compared with 1-butyl-3-methylimdazolium chloride([Bmim]Cl), and some diluents or catalysts are added to the ILs in order to dissolve the biomass quickly. In this research, dissolution of cornstalk and regeneration cellulose rich material (CRM) in the acetie-based ionic liquids like 1-allyl-3-methylimdazolium chloride([Amim]Cl) were made, and investigated the impact on the additive TBD, the results showed that the cellulose content of CRM increased from 24.63% to 32.23%, and the characterization of CRM by SEM, XRD, IR indicated that addition of TBD to [Amim][OAc] has definite help for dissolving cornstalk compared with pure [Amim][OAc].

References

1. Wang XJ, Li HQ, Cao Y, Tang Q. Cellulose extraction from wood chip in an ionic liquid 1-allyl-3-methylimidazolium chloride ([Amim]Cl), Bioresource Technology 102(2011) 7959-7965

2. Li WY, Sun N, Stoner B, Rogers RD, Rapid dissolution of lignocellulosic biomass in ionic liquids using temperature above the glass transition of lignin, Green Chem., 2011: 13, 2038- 2047