Effect of Organic Solvent in Ionic Liquid on Biomass Pretreatment

Pretreatments of corncob and rice straw with cosolvents of ionic liquids and organic solvents were studied. The effects of the organic solvent type, organic solvent fraction in ionic liquid, and reaction temperature on product yield and properties were also examined. The mixtures of 1-ethyl-3-methylimidazolium acetate (EMIM-AC)/dimethylacetamide (DMA) at 40–60 vol % DMA added provided relatively similar values of sugar yield and conversion, extracted lignin content, and yield of regenerated biomass compared with those of EMIM-AC. However, the mixtures of EMIM-AC/ethanolamine (60/40 vol %) and 1-butyl-3-methylimidazolium chloride (BMIM-Cl)/ethanolamine (60/40 vol %) rendered greater enhancements of biomass pretreatment than their ionic liquids. It was also found that various benefits are gained with the use of ionic liquid/organic solvent as a cosolventlow viscosity (giving eases of wash out and handle), more loading of cellulose, and high thermal stability (even operated at high temperature of 150 °C).