Phytochemical Synthesis and Application of Aluminum Oxide Nanoparticles in Photocatalytic Oxidation of Ametryn

The present study investigates the phytochemical synthesis of aluminium oxide nanoparticles (Al۲O۳ NPs) using Hibiscus rosa-sinensis leaf extract and their application in the photocatalytic oxidation of ametryn, a herbicide commonly used in sugarcane cultivation. Column studies were conducted to assess the leaching of ametryn through soil, revealing increased mobility in soils with low organic matter content and higher pH. On characterization of synthesized nanoparticles, SEM images revealed agglomerated spherical structures with smooth surfaces, while XRD analysis confirmed the presence of aluminium oxide with a face-centred cubic structure. FTIR results indicated the presence of various functional groups on the surface of the Al۲O۳ NPs, potentially contributing to their stability and biocompatibility. The photocatalytic degradation of ametryn was studied under UV illumination, with Al۲O۳ NPs as the catalyst. The effects of catalyst dosage, pH, and initial herbicide concentration on the degradation efficiency were investigated. The highest removal efficiency of ۸۴.۰% was achieved with a catalyst loading of ۲.۵ g/L at pH ۳, with ۷۴.۲% of COD reduction. Increasing the catalyst dosage from ۰.۵ g/L to ۳.۰ g/L enhanced the degradation efficiency by ۱۷%. The process was found to be more effective under acidic conditions, with a notable reduction in degradation efficacy of ۷.۶% as pH increased from ۲.۵ to ۴.۰. Reusability studies showed that the catalyst could be used for up to five consecutive cycles, with a ۳۷% reduction in degradation efficiency. Kinetic studies revealed that the pseudo-first-order rate kinetic model fit the process.

کلیدواژه ها:

Hibiscus rosa-sinesis ، Photocatalytic oxidation ، nanoparticles ، Aluminium nanoparticles ، herbicides ، Ametryn