Comprehensive adsorption and spectroscopic studies on the interaction of magnetic biochar from black wattle sawdust with beta-blocker metoprolol

Cristiane Ferraz de Azevedo; Daniel Lucas Costa Rodrigues; Leandro Lemos Silveira; Eder Claudio Lima; Alice Goncalves Osorio; Robson Andreazza; Claudio Martin Pereira de Pereira; Tais Poletti; Fernando Machado Machado

doi:10.1016/j.biortech.2023.129708

Comprehensive adsorption and spectroscopic studies on the interaction of magnetic biochar from black wattle sawdust with beta-blocker metoprolol

Bioresour Technol. 2023 Nov:388:129708. doi: 10.1016/j.biortech.2023.129708. Epub 2023 Aug 23.

Authors

Cristiane Ferraz de Azevedo¹, Daniel Lucas Costa Rodrigues², Leandro Lemos Silveira², Eder Claudio Lima³, Alice Goncalves Osorio², Robson Andreazza⁴, Claudio Martin Pereira de Pereira⁵, Tais Poletti⁶, Fernando Machado Machado⁷

Affiliations

¹ Technology Development Center, Federal University of Pelotas, 1 Gomes Carneiro St., 96010-610 Pelotas, RS, Brazil. Electronic address: cazevedo.iqg@ufpel.edu.br.
² Technology Development Center, Federal University of Pelotas, 1 Gomes Carneiro St., 96010-610 Pelotas, RS, Brazil.
³ Institute of Chemistry, Federal University of Rio Grande do Sul, 9500 Bento Gonçalves Av., Postal Box 15003, 91501-970, Porto Alegre, RS, Brazil.
⁴ Center of Engineering, Federal University of Pelotas, 989 Benjamin Constant St., 96010-020 Pelotas, RS, Brazil.
⁵ Hub Innovat B³, Center for Chemical, Pharmaceutical and Food Sciences, Bio-Forensic Research Group, Federal University of Pelotas, 96160-000, Pelotas, RS, Brazil.
⁶ Technology Development Center, Federal University of Pelotas, 1 Gomes Carneiro St., 96010-610 Pelotas, RS, Brazil; Hub Innovat B³, Center for Chemical, Pharmaceutical and Food Sciences, Bio-Forensic Research Group, Federal University of Pelotas, 96160-000, Pelotas, RS, Brazil.
⁷ Technology Development Center, Federal University of Pelotas, 1 Gomes Carneiro St., 96010-610 Pelotas, RS, Brazil. Electronic address: fernando.machado@ufpel.edu.br.

PMID: 37625653
DOI: 10.1016/j.biortech.2023.129708

Abstract

The rise of contaminants of emerging concern in water-resources due to human activities has driven research toward wastewater treatment, specifically adsorption. The utilization of woody biomass for biochar production in adsorption has shown promise due to its high availability. This study shows the preparation of magnetic biochars (MB) from waste black wattle sawdust, utilizing ZnCl₂ and NiCl₂ (proportions: 1:0.5:0.5 = MB-0.5 and 1:1:1 = MB-1) as activating and magnetic agents. Synthesized via microwave-assisted-pyrolysis, MB boasts a high surface area (up to 765 m².g^-1) and functional groups, enhancing metoprolol medicine adsorption. Nonlinear kinetic and isothermal models were tested; the Avrami fractional-order kinetic model and Liu's isothermal model provided the best fits for experimental data. Thermodynamics and spectroscopic studies revealed spontaneous and exothermic adsorption processes, with physisorption magnitude and dominance of hydrogen-bond and π-π-interactions. MB can be easily extracted from an aqueous medium using magnetic fields, while adsorption capacity could be regenerated through green solvent elution.

Keywords: Emerging contaminants; Low-cost biomass; Magnetic properties; Nonlinear isotherm fitting; Single-step pyrolysis.