Effective Removal of Glyphosate from Aqueous Systems Using Synthesized PEG-Coated Calcium Peroxide Nanoparticles: Kinetics Study, H2O2 Release Performance and Degradation Pathways

Fan Li; Thomas Shean Yaw Choong; Luqman Chuah Abdullah; Siti Nurul Ain Md Jamil; Nurul Nazihah Amerhaider Nuar

doi:10.3390/polym15030775

Effective Removal of Glyphosate from Aqueous Systems Using Synthesized PEG-Coated Calcium Peroxide Nanoparticles: Kinetics Study, H₂O₂ Release Performance and Degradation Pathways

Polymers (Basel). 2023 Feb 3;15(3):775. doi: 10.3390/polym15030775.

Authors

Fan Li¹, Thomas Shean Yaw Choong^{1

2}, Luqman Chuah Abdullah^{1

2}, Siti Nurul Ain Md Jamil^{3

4}, Nurul Nazihah Amerhaider Nuar³

Affiliations

¹ Department of Chemical and Environmental Engineering, Faculty of Engineering, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia.
² Institute of Tropical Forestry and Forest Product (INTROP), Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia.
³ Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia.
⁴ Centre of Foundation Studies for Agricultural Science, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia.

Abstract

Glyphosate (N-phosphonomethyl glycine) is a non-selective, broad-spectrum organophosphate herbicide. Its omnipresent application with large quantity has made glyphosate as a problematic contaminant in water. Therefore, an effective technology is urgently required to remove glyphosate and its metabolites from water. In this study, calcium peroxide nanoparticles (nCPs) were functioned as an oxidant to produce sufficient hydroxyl free radicals (·OH) with the presence of Fe²⁺ as a catalyst using a Fenton-based system. The nCPs with small particle size (40.88 nm) and high surface area (28.09 m²/g) were successfully synthesized via a co-precipitation method. The synthesized nCPs were characterized using transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), Brunauer-Emmett-Teller analysis (BET), dynamic light scattering (DLS), and field emission scanning electron microscopy (FESEM) techniques. Under the given conditions (pH = 3.0, initial nCPs dosage = 0.2 g, Ca²⁺/Fe²⁺ molar ratio = 6, the initial glyphosate concentration = 50 mg/L, RT), 99.60% total phosphorus (TP) removal and 75.10% chemical oxygen demand (COD) removal were achieved within 75 min. The degradation process fitted with the Behnajady-Modirshahla-Ghanbery (BMG) kinetics model. The H₂O₂ release performance and proposed degradation pathways were also reported. The results demonstrated that calcium peroxide nanoparticles are an efficient oxidant for glyphosate removal from aqueous systems.

Keywords: AOPs; H2O2 release; agricultural wastewater; calcium peroxide; kinetics study; nanoparticles.

Grants and funding

This research was funded by the Ministry of Higher Education (KPT), Malaysia under the Fundamental Research Grant Scheme FRGS/1/2020/TK0/UPM/01/2 (03 01 20 2250FR).