Obtenção e caracterização do biocarvão de endocarpo de tucumã modificado com oxone® para adsorção de íons Cu2+ de soluções aquosas

Abstract

Copper plays a crucial role in various industrial processes; however, when present in high concentrations in aquatic ecosystems, it poses a threat to human health and aquatic organisms due to its toxicity and potential for bioaccumulation. In this dissertation, biochar was produced from the endocarp of tucumã-of-Pará (Astrocaryum vulgare) and chemically modified with Oxone® to evaluate its potential for removing Cu²⁺ ions from aqueous solutions. The obtained samples were characterized using Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and surface area analysis (BET). Adsorption experiments were conducted using a central composite design, which showed that pH, adsorbent dosage, and initial copper concentration, as well as their interactions, were statistically significant variables (p < 0.05). Among these, copper concentration and pH had the greatest influence on adsorption capacity. According to the quadratic regression model, R² values of 0.9571 and 0.9410 were obtained for BC and BCO, respectively. More specifically, BC exhibited a maximum adsorption capacity of 38 mg g⁻¹ at pH 2.4 and a concentration of 0.0818 mol L⁻¹, while BCO showed a maximum capacity of 36 mg g⁻¹ under the same conditions. Therefore, although both materials proved to be efficient, BC demonstrated superior performance, indicating that modification with Oxone® is unnecessary for this application.