Articolo in rivista, 2023, ENG, 10.1016/j.jece.2023.110835

An alternative synthesis of magnetic biochar from green coconut husks and its application for simultaneous and individual removal of caffeine and salicylic acid from aqueous solution

Peixoto, Bruno Salarini; Mota, Larissa Silva de Oliveira; Dias, Isac Marinho; Muzzi, Beatrice; Albino, Martin; Petrecca, Michele; Innocenti, Claudia; de Oliveira, Pamella Christina Ortega; Romeiro, Gilberto Alves; Sangregorio, Claudio; (de Moraes, Marcela Cristina

1 Fluminense Fed Univ Outeiro Sao Joao Batista, Chem Inst, BR-24020141 Niteroi, RJ, Brazil 2 CNR, Inst Chem Organometall Cpds, I-50019 Sesto Fiorentino, FI, Italy 3 Univ Florence, Dept Chem Ugo Schiff& INSTM, I-50019 Sesto Fiorentino, FI, Italy

Efficient remediation of water pollutants requires the continuous development of new technologies. Magnetic biochars offer a sustainable solution by combining the high adsorptive capacity of biochar with easy adsorbent recovery. However, the main existing methods for synthesizing magnetic carbons have some disadvantages, such as obtaining materials with a poor magnetic response or with less surface area available for the adsorption of contaminants. Thus, there is an evident need to develop new methods for the synthesis of magnetic carbons. This study presents an innovative approach to obtaining a magnetic nanocomposite (MNC). Initially, chemically activated biochar (ACP) was produced from the pyrolysis of green coconut husks (GCH). Subsequently, an oleic acid-coated magnetite colloid was employed to incorporate magnetic nanoparticles into the porous structure of ACP. Two additional magnetic carbons were prepared using co-pyrolysis of GCH or GCH biochar, both impregnated with FeCl3 solution, for performance comparison. Characterization of MNC revealed a high BET surface area (1019 m(2).g(-1)) and favorable magnetism (11.2 +/- 1.1 emu.g(-1)). The MNC exhibited similar or superior adsorption capacities for caffeine (153 mg.g(-1)) and salicylic acid (203 mg.g(-1)) when compared to the other materials. These findings highlight the ability of this innovative process to provide a material with good magnetic properties and concomitantly high surface area, resulting in a promising adsorbent for the removal of contaminants from water.

Journal of Environmental Chemical Engineering 11 (5), pp. 110835-1–110835-12

Keywords

Activated carbon, Adsorption, Biochar, Biomass, Caffeine, Magnetic biocha, rMagnetic nanocomposite, Salicylic acid

CNR authors

Muzzi Beatrice, Petrecca Michele, Albino Martin, Sangregorio Claudio

CNR institutes

ICCOM – Istituto di chimica dei composti organo metallici