Síntese de material carbonáceo a partir de resíduos da olivicultura para adsorção de contaminantes emergentes

Abstract

The objective of this work was to evaluate the potential of using olive pomace as a precursor in the production of activated carbon for application in the treatment of effluents containing emerging contaminants. The developed adsorbent was characterized through the techniques of Brunauer, Emmett and Teller (BET), Thermogravimetry (TGA), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM), Potential of Zero Load (pHpcz), and specific mass. The results showed the potential of the activated carbon produced as an adsorbent material, with a surface area of 650.9 m2·g−1. For the study of batch adsorption of nimesulide on activated carbon, an experimental design was proposed with the objective of evaluating the influence of pH and initial concentration of the solution containing the contaminant and the adsorbent dosage on the adsorption capacity and removal efficiency. From the same adsorption kinetics and equilibrium tests were performed. The kinetic and equilibrium models that best fitted the experimental data were Elovich and Freundlich, respectively. The maximum adsorption capacity obtained experimentally was 353.27 mg·g−1. A batch adsorption study of ibuprofen was also carried out, similarly to that proposed for nimesulide adsorption. The PSO kinetic model was the one that best fitted the experimental data obtained, and for the equilibrium isotherm, the best fit was obtained for the Langmuir model, which presented a maximum adsorption capacity of 353.91 mg·g−1. In addition, continuous flow adsorption experiments were carried out using a fixed bed column. The mathematical model that best described the behavior of the results obtained was the Thomas, with an adsorption capacity of 167.77 mg·g−1. From the results obtained in this work, it is possible to state that the production of activated carbon from olive pomace showed great potential as an adsorbent material for emerging contaminants. Keywords: Agro-industrial waste. Batch. Fixed bed. Emerging contaminants. Kinetic and equilibrium adsorption.