The growing production and extensive use of herbicides have resulted in their frequent detection in various environmental compartments. N-(phosphonomethyl)glycine (glyphosate, GLY) is one of the most widely used herbicides worldwide. Due to its persistence in aquatic environments and its numerous documented negative effects on ecosystems, as well as potential risks to human health, it is considered a highly concerning organic pollutant. Therefore, it is essential to develop efficient and sustainable methods for its removal from water. Among the promising approaches, heterogeneous photocatalysis is a green method characterized by simplicity, environmental friendliness, and the use of renewable energy, which, through simulated solar irradiation and semiconductor materials, such as TiO₂ photocatalyst, successfully degrades organic pollutants in water.
This study investigates two factors affecting the efficiency of the photocatalytic degradation of GLY: the impact of initial pH value of suspension and the influence of hydrogen peroxide concentration. The influence of catalyst loading (0.5 to 2.0 mg/cm³) on the degradation efficiency was investigated under both acidic and basic conditions, at pH 3 and 10, over a period of 60 min under simulated solar irradiation. The highest removal efficiency was achieved in basic medium with catalyst loading of 2.0 mg/cm3, when 58% of GLY was removed. The impact of hydrogen peroxide concentration was also investigated in the range of 1.0–10.0 mM at catalyst loading of 0.5 and 2.0 mg/cm³ in both acidic and basic medium. After 60 min of irradiation in both media, the most efficient system was the one in which the hydrogen peroxide concentration was 3.0 mM. Overall, the results demonstrate that the photocatalytic degradation of GLY is strongly influenced by both of the investigated factors.
Acknowledgements
The financial support of the Ministry of Science, Technological Development and Innovation of the Republic of Serbia (Grants No. 451-03-137/2025-03/ 200125 and 451-03-136/2025-03/200125).
