Use of Biochar Prepared from the Açaí Seed as Adsorbent for the Uptake of Catechol from Synthetic Effluents

Abstract

This work proposes a facile methodology for producing porous biochar material (ABC) from açaí kernel residue, produced by chemical impregnation with ZnCl2 (1:1) and pyrolysis at 650.0 °C. The characterization was achieved using several techniques, and the biochar material was employed as an adsorbent to remove catechol. The results show that ABC carbon has hydrophilic properties. The specific surface area and total pore volume are 1315 m2·g−1 and 0.7038 cm3·g−1, respectively. FTIR revealed the presence of oxygenated groups, which can influence catechol adsorption. The TGA/DTG indicated that the sample is thermally stable even at 580 °C. Adsorption studies showed that equilibrium was achieved in <50 min and the Avrami kinetic model best fits the experimental data, while Freundlich was observed to be the best-fitted isotherm model. Catechol adsorption on ABC biochar is governed by van der Waals forces and microporous and mesoporous filling mechanisms. The Qmax is 339.5 mg·g−1 (40 °C) with 98.36% removal of simulated effluent, showing that açaí kernel is excellent biomass to prepare good biochar that can be efficiently used to treat real industrial effluents.

Valorização dos resíduos da agroindústria de beneficiamento do açaí: Uma revisão

“…Essa porosidade aumentada confere ao carvão ativado altas propriedades de adsorção, permitindo que ele remova impurezas, compostos orgânicos e poluentes de líquidos e gases. E ainda que Nobre et al (2023) tenham destacado os carvões derivados do caroço de babaçu e castanha do Pará com melhor desempenho, não exclui a capacidade de adsorção do caroço de açaí em remoção de outras substâncias como visto por Feitoza et al (2022), Guerreiro et al (2022), e Guedes et al (2021).…”

“…Ela desempenha um papel fundamental na alimentação diária de uma grande parcela da população na região Norte do Brasil, principal produtora desse superalimento. No cenário mundial, o Brasil ocupa as posições de maior produtor, consumidor e exportador de açaí (Nobre et al, 2023;Feitoza et al, 2022). Em 2022, o país alcançou uma produção anual de cerca de 1,7 milhões de toneladas do fruto (IBGE, 2022).…”

Nickel-aluminium layered double hydroxide as an efficient adsorbent to selectively recover praseodymium and samarium from phosphogypsum leachate

“…However, other mechanisms could be involved in adsorption, further evaluated in the next section. Finally, for both REEs, the changes in the entropy (ΔS°) were negative, which indicates a diminution of the randomness, and a more organized state of the adsorption system, after the REEs are uptaken by Ni-Al-LDH [40][41][42].…”

“…Obtaining the thermodynamic parameters is very important to better understand the temperature's effect on the adsorption process and the nature of the adsorption between REEs and Ni-Al-LDH. For that purpose, Gibbs free energy, entropy, and enthalpy changes were obtained from van't Hoff plot [40] and calculated as previously reported [22,[40][41][42]. Fig.…”

A Statistical Physics Approach to Understanding the Adsorption of Methylene Blue onto Cobalt Oxide Nanoparticles

“…Adsorption is the most widely used technique in the treatment of industrial wastewater at the tertiary stage due to its easy implementation and relatively low cost compared with other techniques [ 1 , 27 , 28 , 29 , 30 , 31 , 32 , 33 ]. Adsorption is among the most widely used techniques and is easy to implement.…”