Development and testing of alginate/C3N4porphyrin bead as a self-initiated Fenton photocatalyst for highly efficient atrazine removal

Jiajie Xu; Zhiyu Liu; Tenghui Jin; Xusheng Yang; Huihuang Chen; J Paul Chen

doi:10.1016/j.scitotenv.2024.173112

Development and testing of alginate/C₃N₄porphyrin bead as a self-initiated Fenton photocatalyst for highly efficient atrazine removal

Sci Total Environ. 2024 Jul 15:934:173112. doi: 10.1016/j.scitotenv.2024.173112. Epub 2024 May 9.

Authors

Jiajie Xu¹, Zhiyu Liu¹, Tenghui Jin¹, Xusheng Yang¹, Huihuang Chen¹, J Paul Chen²

Affiliations

¹ College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China.
² College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen 518060, PR China. Electronic address: jpaulchen@gatech.edu.

PMID: 38734090
DOI: 10.1016/j.scitotenv.2024.173112

Abstract

Fenton reaction has been widely used for efficient treatment of organic wastewater. However, its applications are limited by such key factors as pH < 3. In this study, we developed, tested, and optimized an alginate/C₃N₄porphyrin bead (C₃N₄por-SA) as a recyclable photocatalyst in a photocatalysis-self-Fenton process to overcome these limitations. Porphyrin-modified C₃N₄ (C₃N₄por) was used as the H₂O₂ donator, while Fe(III) nodes served as the Fenton reagent. The as-prepared floating alginate/C₃N₄por bead utilized the light source as a driving force for the catalysis. Under visible light irradiation for 6 h, the model pollutant atrazine was degraded by 70.96 % by the optimized photocatalyst (named as C₃N₄por-SA-Fe1Ca5), demonstrating better photocatalytic performance than alginate/C₃N₄ beads. This improvement was attributed to the higher H₂O₂ yield from C₃N₄por. The alginate/C₃N₄por bead showed better photocatalytic activity even after several consecutive cycles and could easily be recovered for reuse. Furthermore, Fe(III)/Ca(II) bimetallic alginate bead exhibited better photocatalytic activity and a higher content of •OH radicals than the Ca(II) monometallic alginate beads, due to the ability of Fe(III) nodes to serve as a Fenton reagent. The influences of light sources, and commonly existing matters (namely SO₄^2-, Cl^-, CO₃^2-, NO₃^-, and humic acid) were investigated. Moreover, the alginate/C₃N₄por bead demonstrated good photocatalytic performance in a simulated natural environment without the addition of extra H₂O₂, with an atrazine removal percentage of up to 96.3 % after 3-h irradiation. These findings indicated the great potential of alginate/C₃N₄por bead in practical applications.

Keywords: Alginate; Atrazine; C(3)N(4); H(2)O(2) generation; Photocatalysis-self-Fenton.