Development of magnetic carbonaceous adsorbents from CO2 activation

Abstract

Several carbonaceous materials have been developed for the adsorption of pollutants, and among them, magnetic carbons (CM) stand out, whose preparation can be through hydrothermal carbonization (CHT) of biomass and iron salts. Activation of CM can be performed by chemical or physical action, and activation by CO2 has been little explored in the literature, especially for CM obtained from sugarcane bagasse. In this context, the main objective of this project will be the activation with CO2 of carbonaceous material studying the effect of temperature on the properties of the material for use in adsorption. For this, sugarcane bagasse will be used as a carbon source for the preparation of CM by means of CHT in one step, in the presence of iron(III) nitrate solution. After the synthesis of the CM, it will be submitted to the activation process with CO2 under heat treatment at 700 and 900 ºC, during an interval of 1 hour. The CM and the activated magnetic carbons (CMA) will be characterized by X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and nitrogen adsorption-desorption isotherms, followed by a study of the surface functionality using the Blue of Methylene (AM - cationic dye) and Reactive Blue-19 (R-19 - anionic dye), as probe molecules to evaluate the adsorption properties. A batch study will also be carried out to evaluate the adsorbed dose of AM and R-19 dye by CM and CMA. The determination of the concentration of Methylene Blue and Reactive Blue-19 will be done by Ultraviolet/Visible spectroscopy, at 664 and 590 nm, respectively. Additionally, the release of organic substances by the activated carbonaceous material will be evaluated using UV/Vis and Molecular Fluorescence and Total Organic Carbon (TOC) Spectroscopies. It is expected at the end of this project to understand the role of CO2 in the activation of CMA and their respective uses as new adsorbents.(AU)