Materials, Methods & Technologies, Volume 12, 2018

Abstract: A novel, low cost adsorbent, a cerium supported on high porous carbon from fish scales carp (Cyprinus carpio), has been synthesized to remove As(V) ions from water. The synthesis consisted of chemical and thermal treatment for converting the fish scales into the porous carbon decorated by cerium nanoparticles. By changing the reaction conditions, the porosity and the content of the CeO2 nanoparticles may be controlled in synthesized porous carbon. By optimizing the reaction parameters, using the response surface methodology (RSM) where the output is the result of the adsorbent capacity, a highly efficient material (CeO2-HPC) with a capacity of 81.664 mg g-1 (Langmuir isothermal model) was obtained to remove As (V) ions from the drinking water. The adsorption studies were conducted as a function of pH, contact time, mass of adsorbent and temperature. The best sorption of arsenate ions was achieved for pH between 4.0 and 6.0. The adsorption data for arsenate at 25, 35 and 45 °C are fitted to Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherm models. Experimental data were used to model adsorption kinetics using pseudo-first order, pseudo-second order, Elovich and intraparticle diffusion kinetic models. The results showed that the adsorption of As(V) ions onto CeO2-HPC followed the pseudo-second-order kinetic model and Freundlich isotherm models. Thermodynamic parameters, including the Gibbs free energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0) changes, indicated that the present adsorption process was feasible, spontaneous and endothermic in the temperature range of 25-45 °C.