CATALYTIC CONVERSION OF MICROCRYSTALLINE CELLULOSE TO NANOCELLULOSE USING IRON OXIDE CATALYSTS

Abstract

Catalytic conversion of microcrystalline cellulose (MCC) to nanocellulose is a one-pot homogeneous reaction which is done by the cleavage of β-1,4-glycosidic bonds within the cellulose network. This paper shows that by synergistic combination of ultrasonication and catalyst proves effective in the controlled depolymerisation process of cellulose. Iron oxide which is a Lewis acid catalyst was used to abstract the single electron from electron-rich C-O bond in cellulose. The iron oxide was Maghemite (g-Fe₂O3) shows the highest activity as determined by the increase of crystallinity index (CrI%) from 80.62% to 85.63%. The other phases of iron oxide also showed catalytic activity with hematite (Fe₂O₃) at 84.05% and magnetite (Fe₃O₄) at 83.39%. Morphology and particle size analysis clearly shows the nanocellulose obtained ranging from 78nm to 220nm due to the structural dimension measurement of both the thickness (diameter) & length. Spectroscopy analysis via FTIR and Raman shows no changes to the functional group, hence the chemical composition integrity of the cellulose remains intact. Nanocellulose suspension obtained using maghemite shows also the highest colloidal stability and surface tension making it more stable for application.