Adsorption of Zinc Oxide Nanoparticles onto Esterified Carbonize Sago Hampas: Kinetic and Equilibrium Studies

Abstract

: Sago hampas was chemically modified through esterification to adsorb both laboratory and commercial synthesized Zinc oxide nanoparticles from water in a batch adsorption studies. The esterified sago hampas (ECSH) as a bio-sorbent was characterized using Energy-dispersive X-ray spectroscopy (EDX), Fourier-transform infrared spectroscopy (FT-IR), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) technique. Investigating the effect of pH, contact time, initial sorbate ion concentration, temperature and sorbent mass were carried out where adsorption parameters were analyzed using Langmuir, Freundlich and Temkin models. The correlation between Kinetics of adsorption and the rate order of Zinc oxide nanoparticles on ECSH were also determined. The adsorption of Zinc oxide nanoparticles was found to increase with increasing contact time with the attainment of equilibrium at 100 th minute with maximum removal efficiency of 85.5% (0.036 mg/g) and 89.6% (0.106 mg/g) for laboratory and commercial synthesized Zinc oxide nanoparticles from aqueous solution. An optimum pH of 8 with adsorbent dose of 2.0 g at a temperature of 50°C gave good results of Zinc oxide nanoparticles removal. The equilibrium data for both sorbate solutions fitted well for both Langmuir and Freundlich isotherm models. From the Langmuir model, ECSH recorded greater sorption capacity of 0.2 mg/g and 0.6 mg/g for laboratory and commercial synthesized Zinc oxide nanoparticles respectively. The kinetic studies showed pseudo-second order model as the best fitted for the sorption of Zinc oxide nanoparticles for both laboratory and commercial Zinc oxide nanoparticles.