Adsorption properties of sugarcane bagasse and corn cob for the sulfamethoxazole removal in a fixed-bed column

Abstract

Natural adsorbents are a good alternative to remove antibiotic residues from wastewater. In this study, the adsorption capacity of sulfamethoxazole (SMX) onto sugarcane bagasse (SB) and corn cob (CC) in a continuous fixed-bed was compared. Brunauer Emmett Teller, Fourier transform infrared (FTIR), Boehm titration, and point of zero charge (pHpzc) were used to characterize both adsorbents. The adsorption capacity (qe) and the removal percentage of SMX (% R) were investigated at different different flow rates (2, 5, and 7 mL min− 1) and adsorbent masses (4 and 6.4 g), and a constant initial concentration of 5 mg L− 1. The results of the characterization showed that SB has a morphology with more dispersed particles and a specific surface higher than CC (2.6 > 1.2 m2 g− 1). Boehm titration indicates that both the surface of SB and CC have a greater amount of acid groups, which is in agreement with FTIR and pHpzc results. The continuous fixed-bed experiments showed that % R and qe of SMX are higher with SB in all the tests. The highest qe and maximum % R was 0.24 mg g− 1 and 74% with SB, and 0.15 mg g− 1 and 65% using CC. In most cases, the qe of both adsorbents decreased with the increase of flow rate and bed height. An analysis suggests that hydrogen bonds could be the main factor favoring the SMX adsorption with SB. Finally, the intraparticle diffusion was the rate-controlling step, predominating the pore-volume diffusion resistance.

Prospecção Tecnológica sobre o Uso de Bagaço de Cana-de-Açúcar e seus Derivados para a Adsorção Seletiva e Compostos Contendo Enxofre no Diesel

“…Os resultados indicaram que o biocarvão proveniente do bagaço de cana-de-açúcar foi um adsorvente eficaz e de baixo custo. Juela et al (2021) também estudaram as propriedades de adsorção de sulfametoxazol pelo bagaço de cana-de-açúcar e por espigas de milho. Por meio de experimentos em leito fixo contínuo, foi notada uma maior capacidade de adsorção e percentual de remoção de sulfametoxazol ao utilizar o bagaço de cana-de-açúcar.…”

“…A adsorção de sulfametoxazol indica que biocarvões derivados do bagaço de cana-de-açúcar se mostraram eficientes na remoção de compostos orgânicos aromáticos sulfurados, como é o caso dos tiofenos, benzotiofenos, dibenzotiofenos e seus derivados. Além disso, no sulfametoxazol, o enxofre está em seu estado hexavalente (Juela et al., 2021), mesmo estado dos compostos sulfurados presentes no diesel após submetidos a um processo oxidativo (Tanaka, 2018).…”

On the Safe Storage of Bagasse

“…After burning, the ash may be used in the manufacture of building materials [1]. The ash has also recently been employed in column adsorption technologies to remove environmental pollutants such as manganese, cobalt, copper, nickel and sulfamethoxazole from water (see [9, 14]). An obvious use is as a fuel from which to generate electricity and steam to run the sugar extraction process.…”