Green Surface-engineered Nanocellulose From Raphia Farinifera Inflorescence for Mechanistic Control of Interfacial Chemistry in Sustainable Water Treatment
Year: 2026
Type: article
Abstract: This record presents research on green, surface-engineered nanocellulose derived from Raphia farinifera inflorescence for the selective capture of heavy-metal ions from water. Cellulose nanocrystals (CNC) were isolated from this agro-waste biomass and surface-functionalised by TEMPO-mediated oxidation to introduce carboxylate (C6 –COO⁻) groups that act as high-density metal-binding sites. The work characterises how divalent heavy-metal ions bind to these carboxylated surfaces, showing that uptake proceeds predominantly by inner-sphere coordination – direct, partly covalent metal–oxygen bonds to deprotonated C6-carboxylate donors - rather than by simple electrostatic attraction. Adsorption behaviour is analysed through isotherm, kinetic, and thermodynamic modelling, complemented by FTIR evidence of surface complexation. A central finding is that binding strength tracks the covalent/polarisation character of the metal–oxygen interaction, which decreases across the series Pb²⁺ > Cu²⁺ > Cd²⁺ > Ni²⁺ > Zn²⁺. This ordering departs from the classical electrostatic (Irving–Williams) expectation and is interpreted through a frontier-orbital (HSAB) framework, providing a predictive, softness–affinity basis for designing selective bio-based adsorbents. The materials were further evaluated in real Nigerian water matrices to assess performance under environmentally relevant conditions. Together, the results support the use of abundant, renewable lignocellulosic waste as a route to low-cost, selective sorbents for heavy-metal remediation. This deposit accompanies a conference poster presented at GreenIUPAC 2026.
Institution: Enugu State University of Science and Technology
Language: English
Subfield: Water Science and Technology
Field: Environmental Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7208837511