Magnetic NiFe₂O₄/MWCNTs functionalized cellulose bioadsorbent with enhanced adsorption property and rapid separation

Magnetic NiFe₂O₄ nanoparticles and multi-walled carbon nanotubes functionalized cellulose composite (m-NiFe₂O₄/MWCNTs@cellulose) as a magnetic bioadsorbent was prepared and used for effectively removing Congo Red (CR) from aqueous solution. The chemical and physical properties of the prepared m-NiFe₂O₄/MWCNTs@cellulose were characterized by XRD, TGA, FT-IR, VSM, SEM and TEM. Batch experiments were carried out to investigate the adsorption capacity and mechanisms. Effects of different adsorption parameters such as initial CR concentration, adsorbent dosage and temperature were studied. Results demonstrated that m-NiFe₂O₄/MWCNTs@cellulose had high adsorption capacity for CR from aqueous solution. The obtained experimental data fitted well with the pseudo-second-order equation and followed the Langmuir isotherm model with a maximum adsorption capacity of 95.70 mg g^-1 for CR. The m-NiFe₂O₄/MWCNTs@cellulose with rapid magnetic separation and high adsorption capacity can be a promising and recyclable engineering biomaterials for purification and treatment of practical wastewater.