Recent development in the formation and surface modification of cellulose-bead nanocomposites as adsorbents for water purification: a comprehensive review

Abstract Water pollution is an issue of global concern that demands effective and sustainable solutions through water purification. Adsorption is a popular method for water treatment because it is inexpensive and has a high performance rate. Although commercial activated carbon is the generally preferred adsorbent for adsorption, its widespread use is affected by the high cost and challenges encountered during column adsorption. Biopolymers like cellulose and its derivatives have the potential to replace expensive adsorbents due to their unique characteristics. In recent years, cellulose-bead nanocomposites have gained significant attention as promising adsorbents due to their ability to circumvent the challenges encountered when using powdered adsorbents. To fabricate cellulose beads, cellulose fiber is separated from its source, dissolved in appropriate solvents, shaped into spherical particles and subsequently modified (via esterification, oxidation, crosslinking agents, etc.) to improve its adsorption capacity. This comprehensive review paper presents a detailed analysis of the recent development in the formation and surface modification of 3-D structured cellulose nanocomposites. The outcome of this review on modified cellulose-bead demonstrates their successful fabrication and high adsorption capacities for different contaminants. It is anticipated that cellulose beads, as a bio-adsorbent in industrial settings, will be a low-cost alternative to the more expensive adsorbents shortly.