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Bisphenol-A (BPA) is a common plasticizer that has been considered a chemical of concern due to its endocrine disruption potential. In this sense, this paper aimed to investigate the adsorption of this contaminant onto commercial organophilic clay named Spectrogel® as means of water remediation. For this, characterization techniques were carried out before and post-process to identify any major alterations to the adsorbent due to BPA uptake. A statistical central composite rotational design (CCRD) technique was performed for process optimization. The impact of adsorbent dosage mass (0.128–1.472 g.100 mL−1, solution concentration (0.064–0.736 mmol/L−1) and particle diameter (0.28–1.0 μm) on the adsorption capacity was analysed. It was defined 0.064 g of adsorbent dosage and an average particle size of 0.855 μm as optimum conditions, in which a 0.193 mmol.g−1 (44.060 mg.g−1) adsorption capacity was obtained. Static adsorption assays showed that the kinetics better followed the external mass transfer resistance model, whilst the isotherm data obtained at 15 and 25 °C were well expressed by the Freundlich model and at 40 and 55 °C by the D-R model, achieving a maximum adsorptive capacity of 0.4 mmol.g−1 (91.316 mg.g−1). The thermodynamic parameters reflected a spontaneous and endothermic process. Furthermore, numerous eluent solutions were tested to assess the regenerability of the adsorbent and sodium hydroxide displayed the best desorption capacity (77.8%). The Spectrogel® clay has shown to be very promising as an alternative adsorbent in the remediation of water contaminated with BPA. |
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