Mitigation of phytotoxicity and enhanced removal of tetracycline from wastewater using magnetic activated carbon derived from Peltophorum pterocarpum leaves

Abstract This research explores the synthesis, characterization, and application of magnetic activated carbon adsorbent prepared from the leaves of Peltophorum pterocarpum for tetracycline (TC) removal from wastewater. The material exhibited a high surface area (1022.36 m 2 /g) and well–developed porous morphology, confirming its mesoporous structure. XPS analysis indicated interactions between Fe 3 O 4 and TC molecules. The superparamagnetic nature of the adsorbent allowed efficient separation from solution. Adsorption experiments showed rapid and effective TC uptake, with maximum monolayer capacity of 123.32 mg/g based on the Langmuir model. Kinetic data followed the pseudo-second-order model, and the Freundlich isotherm suggested multilayer adsorption on a heterogeneous surface. In hospital effluent, the adsorbent achieved 90.0 mg/g adsorption, demonstrating performance under real-water conditions. Regeneration studies showed the material retained 58.5 mg/g capacity after five cycles, highlighting its reusability. Phytotoxicity assessments revealed reduced TC toxicity, with increased seed germination compared to untreated wastewater, indicating environmental safety. These results underscore the potential of the prepared adsorbent as a scalable, efficient, and environmentally friendly adsorbent, combining high adsorption capacity, magnetic recoverability, and long-term reusability for effective pharmaceutical wastewater treatment.