Synthesize and Application of SiO2/CPW Nanocomposite for Removal of Cadmium from Industrial Wastewater

Abstract

The coconut peel waste (CPW) was chemically spiked with silica nanoparticles to develop a novel nanocomposite (SiO2/CPW). The new nanocomposite was characterized by FTIR, SEM and Dynamic Light Scattering method. Adsorption of Cd ions onto SiO2/CPW was studied in batch mode as a function of pH, contact time, adsorbent dosage and initial concentration and temperature. The maximum removal of Cd2+ions was at pH=6.5 and adsorbent dosage=0.1 g. The experiments showed that the adsorption process was quick and about 74.5% of total cadmium was removed within 5 min. Cadmium uptake by the new adsorbent was best described by pseudo-second order model. Using the equilibrium concentration constants obtained at different temperatures, various thermodynamic parameters have been calculated. The results indicated that Cadmium adsorption was feasible, spontaneous, and endothermic. The suggested sorbent proved the great potential in cadmium removal from water and wastewater.