Novel preparation and characterization of cellulose microparticles functionalized in ionic liquids

Ionic liquid (IL)-reconstituted acrylic acid (AA)-functionalized cellulose microparticles were successfully prepared by a water-in-oil suspension technique preliminary modification with AA in homogeneous condition. Cellulose was fully dissolved in 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) IL, and subsequently was grafted homogeneously with AA and N,N'-methylenebisacrylamide (N,N'-MBA) initiated with ammonium persulfate. The grafted cellulose was spheroidized using white silicone oil as the dispersion medium and Span 80 as a dispersant and then reconstituted from [Bmim]Cl. Reaction conditions were optimized to obtain microparticles with both the highest possible grafting efficiency and most uniform bead sizes. Fourier transform infrared spectroscopy, scanning electron microscopy, and an optical microscope were employed to provide structural information for the functionalized IL-reconstituted cellulose microparticles. These microparticles were shown to behave as good sorbents for Cu(II), Ni(II), Fe(III) ions.