Adsorption of Cr (III) and Cd (II) Ions using Mesoporous Cobalt-Ferrite Nanocomposite from Synthetic Wastewater

Hossein Esmaeili,Iman Khoshkerdar

doi:10.17344/acsi.2018.4795

Abstract

In this study, cobalt-ferrite nano-composite (CFNC) is used to adsorb chromium and cadmium ions from synthetic wastewater. Adsorptive characteristics of CFNC are determined by various analysis including SEM, FTIR, VSM and BET. Also, effect of different parameters such as solution pH, buffer volume, electrolyte dose, the initial ion concentration, contact time, the adsorbent dose and temperature were studied on adsorption process. The results showed that the maximum recovery of Cd(II) and Cr(III) ions were determined as C0 = 20 mg/L, t = 50 min, T = 25 °C, CFNC dosage = 20 g/L, and pH = 7 (for Cr(III)) and 6 (for Cd(II)). In these conditions, the amount of 100% Cr(III) and Cd(II) were removed from the aqueous solution. Also, the equilibrium study showed that the adsorption process followed the Langmuir model and the maximum adsorption capacity for Cr(III) and Cd(II) ions were obtained 217 and 303 mg/g, respectively which show very high adsorption capacities. In addition, adsorption kinetics showed that the pseudo first-order kinetic model was better than the pseudo second-order kinetic model. Moreover, thermodynamic studies showed that the adsorption process was possible, spontaneous and endothermic.

Highlights

After fast growth of population and industrialized societies, releasing heavy metals in water ecosystem is one of the most important concerns of the environment
The purpose of this study is to investigate the effect of cobalt-ferrite nanocomposite (CFNC) as a magnetic adsorbent for the removal of chromium (III) and cadmium (II) ions from synthesis wastewater
By BET analysis, the specific surface area of cobalt-ferrite nano-composite (CFNC) was measured 17.84 m2/g. Various parameters such as pH of the solution, type and volume of buffer, type and concentration of the electrolyte, the initial concentration of metal ions in solution, contact time, sorbent dose and temperature were studied on the removal of chromium and cadmium ions from aqueous solution using CFNC

Summary

Introduction

After fast growth of population and industrialized societies, releasing heavy metals in water ecosystem is one of the most important concerns of the environment. Cr (III) ions are in modern industrial as leather and oil purification and Cd (II) ion is widely used in various industries like as metallurgy, dye industry, and making battery, so that wastewater of these industries is polluted by a lot of Cr (III) and Cd (II) ions.[3] Environmental protection agency (EPA) and world health organization (WHO) identify the admissible value of Cr (III) and Cd (II) ions in drinking water as 0.1 and 0.003 mg/L, respectively.[4,5] In oxidation state, Cr (III) is completely insoluble, and it deposits This ion is less detrimental in nature, but a high concentration of chromium ion (III) is hazardous.[6] Increasing heavy metals concentration in water cause that health on a human is in danger. Adsorption capacity, selectivity, equilibrium time and recovery depend on characteristics of sorbent materials

Objectives

Methods

Results

Conclusion