Development and Analysis of Cellulosic Nanocomposites Derived from Plantain Waste for Effective Heavy Metal Removal from Battery Effluent.
Abstract: This study presents the development and characterization of nano adsorbents based on silver nanoparticles (Ag NPs) and silver-cellulose nanocrystals (Ag-CNCs) impregnated on carbon nanotubes (CNTs). The preparation of these adsorbents involved a combination of green chemistry protocols and chemical vapor deposition techniques, followed by thorough characterization using HRTEM, HRSEM, XRD, EDS, and SAED.
The primary objective of this research is to assess the adsorption capabilities of the silver-carbon nanotubes (Ag-CNTs) and the modified multiwalled carbon nanotube-silver-cellulose nanocrystals (Ag-CNTs-CNCs) nanocomposites. These nanocomposites were tested for their efficiency in rapidly removing selected heavy metals (Fe, Cu, Ni, Zn, and Pb) and analyzing various physico-chemical parameters (e.g., pH, total dissolved solids (TDS), chemical oxygen demand (COD), biochemical oxygen demand (BOD), nitrates, sulphates, and chlorides) from battery effluent using a batch process.
The study focused on utilizing plantain waste-based cellulosic nanocomposites as an eco-friendly solution for the removal of heavy metals from battery effluent. The results revealed successful deposition of Ag and the grafting of CNCs into the CNTs matrix, as confirmed by the microstructures, morphology, crystalline nature, and elemental characteristics of the Ag-CNTs-CNCs nanocomposites.
Optimal batch adsorption parameters were determined, with a contact time of 90 minutes and an adsorbent dosage of 0.03 g for Ag-CNTs and a contact time of 90 minutes and an adsorbent dosage of 0.02 g for Ag-CNTs-CNCs. The adsorption capacities for various heavy metals were evaluated as follows for Ag-CNTs: Fe2+ (105.263 mg/g), Cu2+ (238.095 mg/g), Ni2+ (166.667 mg/g), Zn2+ (121.951 mg/g), and Pb2+ (119.048 mg/g). Meanwhile, for Ag-CNTs-CNCs, the adsorption capacities were determined as follows: Fe2+ (200.000 mg/g), Cu2+ (263.158 mg/g), Ni2+ (238.095 mg/g), Zn2+ (169.492 mg/g), and Pb2+ (181.818 mg/g). These results indicate that Ag-CNTs-CNCs exhibited a higher adsorption capacity, primarily attributed to physical adsorption, electrostatic interactions, and surface complexation.
Furthermore, the experimental data was best described by the Langmuir isotherm and pseudo-second order kinetic model for Ag-CNTs, indicating chemisorption and monolayer adsorption. On the other hand, the Freundlich isotherm and pseudo-second order kinetic model were found to best describe the batch adsorption data for Ag-CNTs-CNCs, supporting the chemisorption and multilayered nature of the adsorption process.
Finally, the high physico-chemical parameters present in the effluent were effectively analyzed in the batch systems, ensuring they fell within the permissible concentrations set by the World Health Organization (WHO). Overall, this study highlights the efficiency of Ag-CNTs-CNCs for the treatment of industrial effluent, outperforming Ag-CNTs as an effective adsorbent.
Development and Analysis of Cellulosic Nanocomposites Derived from Plantain Waste for Effective Heavy Metal Removal from Battery Effluent.