Abstract
This article describes the immobilization of magnetite (Fe 3 O 4) nanoparticles on TEMPO-oxidized cellulose nanofiber (TEMPO-CNF) through the co-precipitation of iron salts by the alkaline medium. TEMPO-CNF and TEMPO-CNF/Fe 3 O 4 were confirmed by XRD, TGA, SEM, TEM, BET, and AFM. Characterization of the samples successfully showed the preparation of cellulose nanofibers with a diameter ranging from 10-15 nm and homogenous and uniform magnetic nanoparticles with a diameter of ~ 10 nm. The ability of the synthesized nanocomposite for methylene blue (MB) adsorption, as a cationic dye model, was examined. At pH 7, the highest adsorption efficiency was observed. The isotherm, kinetic models, and enthalpic contributions were calculated to evaluate adsorption experiments. With an adsorption capacity of around 303 mg/g, pseudo-second-order, and Langmuir isotherm provided the best interpretation adsorption process. In addition, the thermodynamics parameters have been evaluated from direct measurement based on Isothermal Titration Calorimetry. The current results showed that TEMPO-CNF/Fe 3 O 4 nanocomposite is a promising green bioadsorbent for organic dye removal for water purification.