.png){kind=icon}
.png){kind=icon}
Return
Green-synthesized Fe3O4/AC/zeolite nanocomposite for efficient tetracycline removal from real pharmaceutical wastewater
.png){kind=icon}
PRE
AI
DOI：10.1016/j.rechem.2026.103272.png)
.png){kind=icon}
Original request for help.png){kind=icon}
Share.png){kind=icon}
Save
Abstract
En 中文
Tetracycline (TC), a commonly used antibiotic, frequently contaminates aquatic environments, raising concerns for ecological and public health due to its persistence and potential to promote antimicrobial resistance. In this study, a sustainable magnetic Fe3O4/activated carbon/zeolite (Fe3O4/AC/Zeo) nanocomposite was developed using Aloe vera extract to efficiently remove TC from synthetic solutions and real pharmaceutical wastewater. The nanocomposite was characterized using BET, SEM, FTIR, and XRD, confirming a high surface area (520.42 m(2)& centerdot;g(-1)), hierarchical porosity, and abundant surface functional groups. Process optimization using response surface methodology (RSM) with central composite design (CCD) identified pH and initial TC concentration as the most significant factors (p < 0.0001). Within the experimental design range (adsorbent dosage: 0.2-1.0 g & centerdot;L-1), optimal conditions were determined as pH 7, dosage 1.0 g & centerdot;L-1, temperature 35 degrees C, contact time 90 min, and initial TC concentration 100 mg & centerdot;L-1 (85-87% removal). For practical pharmaceutical wastewater treatment, the dosage was strategically enhanced to 2.0 g & centerdot;L-1, achieving similar to 90% removal in synthetic solution and 82% in real wastewater under the same operational parameters. Kinetic studies revealed pseudo-second-order behavior (R-2 > 0.999), indicating rate-limiting surface interactions. Isotherm analysis showed favorable Langmuir monolayer adsorption with a maximum theoretical capacity of 80.65 mg & centerdot;g(-1) at 25 degrees C. Thermodynamic parameters indicated spontaneous (Delta G degrees = -2.26 to -0.25 kJ & centerdot;mol(-1)) and exothermic (Delta H degrees = -22.34 kJ & centerdot;mol(-1)) adsorption. The adsorption behavior is consistent with multiple interaction pathways, including electrostatic attraction, hydrogen bonding, pi-pi interactions, and possible coordination interactions. To the best of our knowledge, this is among the first studies to combine green Aloe vera-based synthesis with Fe3O4/AC/Zeo hybridization and application to real pharmaceutical effluent, highlighting its novelty and practical value. These findings demonstrate the potential of the developed nanocomposite as a cost-effective, magnetically recoverable, and environmentally sustainable solution for antibiotic-contaminated water.
Keywords:
Tetracycline removal
Magnetic nanocomposite
Adsorption process
Green synthesis
Pharmaceutical wastewater treatment
Response surface methodology (RSM)