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In the present article, the adsorbent prepared from laterite with lanthanum and cerium oxides (La2O3-CeO2/laterite (LCL)) was efficiently employed for the removal of arsenite and fluoride from an aqueous environment. The obtained materials were characterized by XRD, SEM, and nitrogen adsorption/desorption. The synthesized LCL exhibited a high adsorption capacity towards arsenite (As(III)) and fluoride. The adsorption of both analytes on LCL, which was well-fitted to a pseudo-second-order equation, was found to be kinetically fast in the first 20 minutes and reached equilibrium at around 180 minutes. Weber’s intraparticle diffusion model in multilinearity using the piecewise linear regression combined with Akaike’s criteria was addressed. The adsorption capacities of LCL calculated from Langmuir’s isotherm model were found to be 67.08 mg·g-1 for arsenite and 58.02 mg·g-1 for fluoride. Thermodynamic parameters presented an endothermic nature of arsenite adsorption but an exothermic nature for fluoride and a negative Gibbs free energy for the spontaneous process of arsenite or fluoride adsorption at the studied temperature range. The excellent adsorption performance and stability make the composite of laterite and La-Ce binary oxides an alternative efficient and cheap adsorbent for the removal of arsenite and fluoride in an aqueous solution.

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The synthesis of nanosize single phase CeO 2 by gelatine gel combustion method was investigated. The prepared material was characterized by X-ray diffraction, thermogravimetric and differential thermal analysis, scanning electron microscopy and transmission electron microscopy measurements. At optimum conditions, such as pH 3, the molar ratio of Ce 4+ /gelatine 1/1, and a calcination temperature of 550 o C for 2 hours, the material with average size < 30 nm was synthesized. From the results of phosphate adsorption, adsorption equilibrium time of the material was determined at 60 minutes. The phosphate adsorption process in aqueous solution followed the Langmuir isothermal model with Q max = 152.66 mg/g.