Magnetic Fe₃O₄@Chitosan Carbon Microbeads: Removal of Doxycycline from Aqueous Solutions through a Fixed Bed via Sequential Adsorption and Heterogeneous Fenton-Like Regeneration

Abstract

The adsorptive removal of antibiotics from aqueous solutions is recognized as the most suitable approach due to its easy operation, low cost, nontoxic properties, and high efficiency. However, the conventional regeneration of saturated adsorbents is an expensive and time-consuming process in practical wastewater treatment. Herein, a scalable adsorbent of magnetic Fe3O4@chitosan carbon microbeads (MCM) was successfully prepared by embedding Fe3O4 nanoparticles into chitosan hydrogel via an alkali gelation-thermal cracking process. The application of MCM composites for the adsorptive removal of doxycycline (DC) was evaluated using a fixed-bed column. The results showed that pH, initial concentration, flow rate, and bed depth are found to be important factors to control the adsorption capacity of DC. The Thomas and Yoon-Nelson models showed a good agreement with the experimental data and could be applied for the prediction of the fixed-bed column properties and breakthrough curves. More importantly, the saturated fixed bed can be easily recycled by H2O2 which shows excellent reusability for the removal of doxycycline. Thus, the combination of the adsorption advantage of chitosan carbon with catalytic properties of magnetic Fe3O4 nanoparticles might provide a new tool for addressing water treatment challenges.

Metal oxide/chitosan composite for organic pollutants removal: A comprehensive review with bibliometric analysis

“…Another study used the same treatment, to remove Doxycycline (antibiotic) using Magnetic Fe3O4@chitosan carbon microbeads [77]. The results showed that the adsorption capacity increased as the pH value increased, from 2 to 11.…”

Mesoporous chitosan/activated charcoal powder and bead modified in 1‐butyl‐3‐methylimidazolium acetate for the adsorption of acid blue 25 from an aqueous solution

“…14,16 Physical modifications featuring conversion of chitosan into various forms such as flake, sponge, bead and membrane have also been carried out to enhance the stability of chitosan. 10 Among all these physical forms of chitosan and chitosan-based adsorbent materials, the bead form has gained more attention recently because of its improved mechanical and chemical stability [17][18][19][20][21] on one hand, and adequate separation and heterogeneity of the adsorbent from solution on the other hand. 14 In this regard, modification of chitosan-activated charcoal composite into a bead could also offer assistance in achieving better stability for chitosan, as this may also include preventing the leaching of a functional component of activated carbon.…”

Remoción de fosfatos en aguas residuales domésticas con carbón activado de endocarpio de aceituna modificado con nanopartículas de hierro (III)

“…El rendimiento de las columnas de lecho fijo se analiza por medio de curvas de avance "S" (ruptura o agotamiento), donde es representado por medio de la concentración del efluente en un intervalo de tiempo establecido (Patel, 2019). En la Figura 6, se representa una curva de avance (C/C0 ~ frente al tiempo), MTZ indica la zona de saturación, el punto de ruptura (tb) y punto de saturación (te) acontece cuando C/C0 = 0.05 y C/C0 = 0.9, respectivamente (Bai et al, 2018;Tan & Hameed, 2017).…”