Biochar Obtained from Caryocar brasiliense Endocarp for Removal of Dyes from the Aqueous Medium

Abstract

Given the increase in environmental pollution, especially of water, the emergence of studies that seek to develop strategies to mitigate/treat such effects have gained prominence in the world scientific community. Among the numerous adsorption processes, those made from biochar production stand out. This study analyzed the adsorption properties of the blue methylene model dye in the aqueous solution of biochar and activated biochar developed from pequi (Caryocar brasiliense) endocarp. The biochar was characterized, before and after adsorption, by infrared spectroscopy (FTIR), scanning electron microscopy (SEM), X-ray diffractometry (XRD), and thermogravimetric analysis (TG). The surface load of the materials was performed by the point of zero charge (pHPZC) method. The study also included analyses of contact time parameters and adsorbed concentration in the adsorption process. Morphological analysis showed that a more significant and profound number of fissures and pores appeared in the activated biochar compared to the biochar. Residual mass analysis evidenced that biochar lost about 15% more mass than the activated biochar, indicating that activation occurred satisfactorily. The adsorption process was well adjusted by pseudo-second-order kinetics and Langmuir’s isothermal model. The activated biochar achieved an excellent adsorption capacity of 476.19 mg.g−1, thus demonstrating to be a sound system for removing dyes from an aqueous medium.

Using Activated Biochar from Caryocar brasiliense Pequi Almonds for Removing Methylene Blue Dye in an Aqueous Solution

“…The results of the kinetic tests, combined with the analysis of surface charges and the differences in the biochars' morphological characteristics, indicate that the activation process was a success [47,48]. Furthermore, it is essential to point out that these results for the BA and ABA are similar to those found in the literature for biochars and activated biochars used in MB adsorption [15,18,49,50]. The concentration variation adsorption test at constant temperature of biochars (Figure 6b) reveal an enhancement in adsorption capacity.…”

“…A new band emerges at 470 cm −1 , corresponding to C-O-H bending, a characteristic feature of activated biochar. The shift can be attributed to the biochar activation procedure, underscoring inherent structural alterations [18,34].…”

“…After the immersion, the material obtained was separated through filtration and subjected to a drying period of 12 h at 105 • C in an oven. The activation procedure was called activated pequi almond biochar (ABA) [18,23,24].…”

Polissacarídeos Naturais: Anacardium Occidentale L. E Suas Aplicações Na Obtenção De Scaffolds Para Liberação De Fármacos

“…É importante destacar que poluentes atmosféricos, como óxidos de nitrogênio, em que cerca de 95%, se apresentam na forma de monóxido de nitrogênio (NO), são danosos ao meio ambiente, pois atuam na formação da chuva ácida e poluição fotoquímica. Estudos, mostram a eficiência no uso de carvão ativado, em reações de redução dos gases: NO em N 2 e CO 2 (Correa-Navarro et al, 2020;Bernal et al, 2020;El-Nemr et al, 2022;Melo et al, 2022).…”

Black Tea Waste as Green Adsorbent for Nitrate Removal from Aqueous Solutions

“…The adsorption method is a simple, easy-to-use, and scalable method of contaminant removal [ 19 , 24 ]. For the removal of nitrate ions from aqueous solutions, a variety of adsorbents have been used, including hybrid nanocomposites, activated carbon, anionic layer double hydroxide, and magnetic nanoparticles [ 6 , 25 ].…”