Synthesis of Recyclable Magnetic Cellulose Nanofibers from Ionic Liquids for Practical Applications in Separation...

The present study focused on coupling cellulose nanofibers (alternative materials for plastics and metals) with a magnetic ionic liquid (synthesized by a microwave-assisted method) through mixing to yield magnetic cellulose nanofibers (MCNFs) that can be recycled by attracting them to a magnet. Accordingly, two types of ionic liquids were synthesized: (a) 1-butyl-3-methylimidazolium tetrachloroferrate(III) {[bmim] FeCl₄} and (b) 1-glycidyl-3-methylimidazolium tetrachloroferrate {[glmi]FeCl₄}, which were characterized by the fast atom bombardment mass spectrometry (FAB-MS) technique. Impregnation of the cellulose nanofibers with the {[bmim]FeCl₄} ionic liquid caused the latter to be physically adsorbed onto the nanofibers to produce {MCNF@{[bmim]FeCl₄}, whereas the corresponding {[glmi]FeCl₄} ionic liquid was chemically bonded to the cellulose nanofibers to yield magnetic {MCNF@[glmi]FeCl₄} nanofibers. Under the experimental conditions used, the corresponding magnetic moments were 0.222 A m² kg^-1 for {MCNF@ {[bmim]FeCl₄} and 0.095 A m² kg^-1 for {MCNF@[glmi]FeCl₄}.