Cellulose Nanocrystals (CNCs) and Cellulose Nanofibers (CNFs) as Adsorbents of Heavy Metal Ions

The isolation of nanocellulose has been extensively investigated due to the growing demand for sustainable green materials. Cellulose nanocrystals (CNCs) and cellulose nanofibers (CNFs), which have same chemical composition but different morphology, particle size, crystallinity, other properties depending on precursor synthesis method used. In comparison, CNC particles a short rod-like shape smaller dimensions when compared CNF in form fibers. was carried out chemically (hydrolysis method), mechanically (homogenization, ball milling, grinding), both can be modified because they large surface area are rich hydroxyl groups. Modifications were made increase adsorption ability heavy metal ions. Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission (TEM), thermogravimetric (TG), dynamic light scattering (DLS) reveal characteristics morphology CNCs CNFs. success effectiveness process influenced by few factors. These factors include adsorbent structure changes, area, availability active sites adsorbent’s surface, constants, ionic size differences, pH, temperature, dosage, contact time during process. this review, we will discuss CNFs synthesized from various precursors methods, modification application as ion adsorbents, includes suitable isotherm kinetics models effect pH selectivity types