Synthesis and Mechanistic Insights into Metolachlor Adsorption on L-Arginine Functionalized Fe₃O₄/Activated Carbon Nanocomposite

Yagmur F. E., Şenol Arslan D., Ateş N.

International Journal of Environmental Research, cilt.20, sa.6, ss.1-25, 2026 (Hakemli Dergi)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 20 Sayı: 6
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1007/s41742-026-01226-x
  • Dergi Adı: International Journal of Environmental Research
  • Sayfa Sayıları: ss.1-25
  • Abdullah Gül Üniversitesi Adresli: Evet

Özet

Metolachlor is one of the most frequently detected herbicides in drinking water sources, posing a significant environmental

risk. In this study, an L-arginine functionalized magnetic Fe₃O₄/activated carbon nanocomposite (Fe₃O₄/L-Arg@AC) was

synthesized and its metolachlor removal performance was evaluated. The kinetic and equilibrium adsorption mechanisms

of Fe₃O₄/L-Arg@AC for metolachlor removal were investigated comparatively with pure activated carbon (AC-Puriss),

nitric acid modified activated carbon (AC-HNO₃), and Fe₃O₄/L-Arg. Although Fe₃O₄-based, L-arginine functionalized, and

activated carbon-containing systems have been studied in the literature for different pollutants, the use of Fe₃O₄/L-Arg@

AC composite for metolachlor removal is limited. FTIR analyses confirmed successful binding of L-arginine functional

groups to the surface, while SEM images revealed that the composite exhibited a more homogeneous distribution and an

improved porous surface morphology. Kinetic analyses showed that adsorption process was not limited to diffusion alone

but was based on a multi-stage mechanism where liquid film and intraparticle diffusion processes acted together. The

functionalized structure exhibited faster mass transfer and more efficient adsorption behavior compared to Fe₃O₄/L-Arg.

Equilibrium data indicated that Freundlich model was more suitable for the composite structure and that heterogeneous

surface properties were dominant. Metolachlor adsorption capacity remained stable under neutral and slightly basic pH

conditions, while it was only minimally affected under acidic conditions. In addition, the synthesized adsorbent exhibited

good reusability with a regeneration efficiency of 93.2% over five consecutive adsorption-desorption cycles. This study

demonstrated the Fe₃O₄/L-Arg@AC composite as an effective, reusable, functional, and viable adsorbent alternative for

metolachlor removal in practical water treatment systems.