Enhanced herbicide removal using an innovative NaP1-Fe3O4-La(OH)3 zeolite: Advances in water treatment and experimental modeling

This study explores the synthesis of a novel and efficient NaP1 zeolite from Austrian fly ash (AFA), composited with Fe 3 O 4 nanoparticles (NPs) and lanthanum hydroxides [La(OH) 3 ]. The composite's efficacy was tested for simultaneously adsorbing glyphosate (GLY), glufosinate (Glu), and aminomethylphosphonic acid (AMPA) from water solution. The inclusion of Fe 3 O 4 NPs and La(OH) 3 enhanced the nanoadsorbent's rapid and effective separation capabilities. Significantly, an innovative kinetic model, the Film-Pore-[Concentration-Dependent] Surface Diffusion Model (FPCDSD), was developed to analyze adsorption mechanisms, aligning with experimental results and accurately predicting adsorption processes in single and competitive scenarios. The model used detailed calculations to evaluate mass transfer resistances, employing parameters like rotation speed, adsorbent dosage, and initial concentrations to correlate adsorption data under various conditions. The study found that adsorption capacity retained 92 % effectiveness after 10 adsorption-desorption cycles, consistent with previous research. Results indicated that electrostatic interactions, herbicide affinity for La and Fe complexes, hydrogen bonding, and surface and pore diffusion likely drive adsorption mechanisms. Laboratory tests showed that Gly achieved the Maximum Residual Level (MRL) of 0.1 μg/L as per the European directive for drinking water with 99.95 % removal efficiency, suggesting that NaP1-Fe 3 O 4 -La(OH) 3 is a highly effective option for water treatment. Software : Blender, Avogadro, ChemDraw/Chem3D Concept : The idea, design, and visualization of this figure were entirely developed by me. Explanation : The graphical abstract visually represents the adsorption of herbicides (Glufosinate, AMPA, and Glyphosate) onto a composite material synthesized from Zeolite, Lanthanum hydroxide [ La(OH)₃], and Iron oxide nanoparticles ( Fe₃O₄). In this illustration, La(OH)₃ is symbolized by the diamond-shaped structures, and Fe₃O₄ is depicted as spherical balls. The image highlights the selective adsorption mechanism of these herbicides onto the composite surface, demonstrating the interaction between the adsorbent components and the pollutants. This visual complements the detailed explanation provided in section 4.3 of manuscript , showcasing how the composite material effectively reduces herbicide pollution through its advanced adsorptive properties. • An innovative, facile, efficient and economically feasible adsorbent is developed. • The effect of NaP1-Fe 3 O 4 -La(OH) 3 adsorbent was explored for removal of Herbicides. • A novel FPCDSD model is applied to examine the mechanism of adsorption. • Gly was reduced to meet the European Union's Maximum Residual Limit of 0.1 μg/L