Characterization of Microcrystalline Cellulose after Pretreatment with Low Concentrations of Ionic Liquid-H2O for a Pyrolysis Process

Microcrystalline cellulose (MCC) samples pretreated by ionic liquid (ILs)-H2O mixtures were studied for application in a pyrolysis process. A 1-ethyl-3-methylimidazolium methanesulfonate [Emim][MeSO3]-H2O mixture with solid acid catalyst Nafion®NR50 was used in the pretreatment process. A lower amount of hydrogen bonding between neighboring pretreated MCC chains resulted from a less ordered cellulose structure, leading to lower crystallinity, decreased molecular weight and reduced thermal stability. The pyrolysis result showed that the yields of char were lower, the average reaction rate increased, and the DTG peak temperature decreased relative to the untreated MCC. The amount and concentration of the hydrogen gas obtained from the pyrolysis of sample 90(20) (4.00 mmol/g-sample) was higher than that obtained from the pyrolysis of the MCC (3.26 mmol/g-sample). This study explores MCC (pretreated by ionic liquid-H2O mixtures) with a recyclable solid acid catalyst under varying pretreatment conditions, as a potential raw feed material, to be applied in the pyrolysis process.