Research On Solution And Conversion Of Biomass In Ionic Liquids

In recent years, With the exploition of fossil fuel resources and rapid consumption ofnon-renewable resources, cellulose has received more attention in chemical researchers.Cellulose is the most abundant biorenewable material, with cheap, degradation andenvironment friendly. Dissolved products have many important applications in the energysources, industrial material, fiber paper, membrane, polymer and paints industries.Butcellulose consists of polydisperse linear glucose polymer chains which form hydrogen-bondedsupramolecular structures. Cellulose is insoluble most common organic liquids.Room temperature ionic liquids (RTILs) namely molten salts, are a class of novelenvironment-friendly”green solvents”, widely used in different chemical processes such asheterogeneous catalysis, organic synthesis, electrochemistry, analytical, chemistry andcellulose macromolecule. Ionic liquids have unique properties: Nonvolatile, nonflammable;Good solvents for a wide range of organic, inorganic materials and polymer; High thermalstability and chemical stability, wide range of liquidus temperatures; The availability of awide and veried structure of Ils. The present work is exploiting the possiblility for ionicliquids to act as a good solvent for cellulose.Four RTILs were synthesized and means of FTIR and Nuclear magnetic resonance wereused to analyse and characterize the composition and atructure. The results indicatedconsistence with expect products. Dissolution of mercerizing reguar in these RTILs wereinvestigated by means of PLM observation.Dissolving rate were calculated in the sametemperature and time. The results showed that [BMIM]Cl was the best solvent under the sameconditions and its dissolving rate was12.2%.Cellulose film, which used [BMIM]Cl as solvent, was detected by FTIR、SEM andTGA,and so do microcrystalline cellulose. Then preliminary performance evaluation wasdone. The results showed that [BMIM]Cl was found to be direct solvent of mercerizingreguar; Thermal stability of regenerated cellulose fiber, which compared with native cellulose,was reduced. The effects of dissolving time and rate were decided by DP; Aperture and porosity in cellulose film were detected.With using mercerizing reguar as raw materials, concentrated sulfuric acid as a catalyst,a series of cellulose acetate with different degrees of substitution were prepared. The resultsshowed that: the reaction temperature was85℃, time was10min, the amount of concentratedsulfuric acid was0.8ml, nhydride to microcrystalline cellulose was25:1, the degree ofsubstitution was close to3.