On the Degradation of Glyphosate by Photocatalysis Using TiO2/Biochar Composite Obtained from the Pyrolysis of Rice Husk

Phuong Thu Le (1) , Duy Ngoc Le (1) , Thi Hue Nguyen (1) , Huyen Thuong Bui (1) , Le Anh Pham (2) , Luong Lam Nguyen (1) , Quoc Son Nguyen (1) , Thu Phuong Nguyen (3) , Thu Hien Dang (1) , Thi Thuy Duong (1, 4) , Marine Herrmann (5, 1, 4) , Sylvain Ouillon (6, 1, 4) , Thi Phuong Quynh Le (7) , Dieu Linh Vo (1) , Huong Mai (1) , Thi Mai Thanh Dinh (3, 1)

1 USTH - University of Science and Technology of Hanoi
2 ICube - Laboratoire des sciences de l'ingénieur, de l'informatique et de l'imagerie
3 Institute for Tropical Technology
4 VAST - Vietnam Academy of Science and Technology
5 LEGOS - Laboratoire d'études en Géophysique et océanographie spatiales
6 ECOLA - Echanges Côte-Large
7 INPC - Institute of Natural Products Chemistry

In this study, titanium dioxide (TiO2) nanoparticles are immobilized onto rice husk biochar (RHB), as a porous support, for the photodegradation of glyphosate under UV light irradiation. The TiO2/RHB composites are prepared by pyrolysis and the sol-gel method. The SEM, XRD, EDX, and FT-IR results confirm the graphene structure of RHB and the formation of 10.61 nm TiO2 nanoparticles on the catalyst support. The effects of operating conditions, including catalyst dosage (3 g L−1, 5 g L−1, 10 g L−1, and 20 g L−1) and different illumination conditions (9 W lamp, 2 × 9 W lamps), on the removal of glyphosate from aqueous solutions were investigated. The photodegradation efficiency of 15 mg L−1 of commercial glyphosate was up to 99% after 5 h of irradiation at pH 3.0, with a TiO2/RHB dosage of 10 g L−1. However, the mineralization efficiency under this condition was lower than the decomposition efficiency of glyphosate, proving the partial degradation of glyphosate into AMPA and other metabolites after 5 h of reaction.

Mots clés: TiO 2 coated biochar; glyphosate; photocatalysis; rice husk biochar

Domaines: Catalyse; Ingénierie de l'environnement

Phuong Thu Le, Duy Ngoc Le, Thi Hue Nguyen, Huyen Thuong Bui, Le Anh Pham, et al.. On the Degradation of Glyphosate by Photocatalysis Using TiO2/Biochar Composite Obtained from the Pyrolysis of Rice Husk. Water, 2021, 13 (23), pp.3326. ⟨10.3390/w13233326⟩. ⟨hal-04369925⟩