Capacity assessment and potential for reuse of calcined Bofe bentonitic clay for adsorption of nickel

This work aims to evaluate different eluents in cycles of nickel adsorption/desorption on calcined Bofe clay. The following eluents were used sequentially for nickel desorption: H2SO4 0.25 mol/L, NaCl 1.0 mol/L, CaCl2 0.10 mol/L, and EDTA 0.10 mol/L. Physical‐chemical characterization analyses of Bofe clay samples were carried out under different conditions to evaluate the effect of the remaining metal on the adsorbent submitted to adsorption/desorption cycles. The adsorbent material was characterized by the following techniques: energy dispersive X‐ray spectroscopy (EDX), thermogravimetry (TG), differential scanning calorimetry (DSC), X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and N2 physisorption (BET). Statistica 5.0 was used as a computational tool to adjust the rate quasi‐chemical solution to the experimental data of the breakthrough curves. From the new function obtained, breakthrough curves for different bed heights could be also simulated. An increase of the clay surface area and a reduction of real density after the passage of the four eluents were observed. Among the tested eluents, NaCl (1 mol/L) presented the highest percentage of desorption (88.08 %). The nickel adsorption/desorption cycles study showed that Bofe clay retains the same nickel adsorption capacity throughout the four evaluated cycles94814571465CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQCOORDENAÇÃO DE APERFEIÇOAMENTO DE PESSOAL DE NÍVEL SUPERIOR - CAPESFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPsem informaçã