Cellulose Nanocomposites From Pentaclethra Macrophylla Benth POD: Synthesis and Adsorption Studies

Global pollution, progressive industrialization and the increasing world populace have led to severe environmental problems including water pollution. In this study, Penthaclethra macrophylla benth (oilbean) pod has been suggested as a possible inexpensive adsorbent for the synthesis of cellulose nanocrystals, for the effective removal of lead at low concentrations, with less post-treatment waste. The synthesized sample was analyzed using X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), Energy dispersive x-ray diffraction (EDX), Transmission electron microscopy (TEM) and Fourier transform infrared (FT-IR) spectroscopy. FTIR spectra revealed many peaks indicating the effective attachment of functional groups containing hydroxyl and oxygen for cellulose nanocrystals. Intense peaks at 2θ = 12.4 ^o , 20.3 ^o and 26.4 ^o represent the typical cellulose-I structure. Surface morphology identified by SEM images revealed a stacked flake-like structure while transmission electron micrographs, indicates clusters of spherical shaped nanoparticles, with particle sizes between 1nm – 10 nm. The peaks in the EDX spectra for carbon, oxygen, and other trace elements corresponded to their respective binding energies. To ascertain the kinetics and rate-determining step of the adsorption processes, experimental data were fitted into the pseudo-first order, pseudo-second order, intraparticle diffusion, and elovich models. Adsorption isotherm modelling showed a favourable heterogeneous adsorption as Freundlich isotherm gave a better linear fit. Thermodynamics study showed that the reaction process is feasible and spontaneous.