Solar-driven semi-conductor photocatalytic water treatment (TiO2, g-C3N4, and TiO2+g-C3N4) of cyanotoxins: proof-of-concept study with microcystin-LR.

Pestana, Carlos J.; Hui, Jianing; Camacho-Muñoz, Dolores; Edwards, Christine; Robertson, Peter K.J.; Irvine, John T.S.; Lawton, Linda A.

Abstract

Cyanobacteria and their toxins are a threat to drinking water safety as increasingly cyanobacterial blooms (mass occurrences) occur in lakes and reservoirs all over the world. Photocatalytic removal of cyanotoxins by solar light active catalysts is a promising way to purify water at relatively low cost compared to modifying existing infrastructure. We have established a facile and low-cost method to obtain TiO2 and g-C3N4 coated floating photocatalysts using recycled glass beads. g-C3N4 coated and TiO2+g-C3N4 co-coated beads were able to completely remove microcystin-LR in artificial fresh water under both natural and simulated solar light irradiation without agitation in less than 2 h. TiO2 coated beads achieved complete removal within 8 h of irradiation. TiO2+g-C3N4 beads were more effective than g-C3N4 beads as demonstrated by the increase reaction rate with reaction constants, 0.0485 min−1 compared to 0.0264 min−1 respectively, with TiO2 alone found to be considerably slower 0.0072 min−1. g-C3N4 based photocatalysts showed a similar degradation pathway to TiO2 based photocatalysts by attacking the C6–C7 double bond on the Adda side chain.

Citation

PESTANA, C.J., HUI, J., CAMACHO-MUÑOZ, D., EDWARDS, C., ROBERTSON, P.K.J., IRVINE, J.T.S. and LAWTON, L.A. 2022. Solar-driven semi-conductor photocatalytic water treatment (TiO2, g-C3N4, and TiO2+g-C3N4) of cyanotoxins: proof-of-concept study with microcystin-LR. Chemosphere [online], 310, article 136828. Available from: https://doi.org/10.1016/j.chemosphere.2022.136828

• Journal Article Type: Article
• Acceptance Date: Oct 7, 2022
• Online Publication Date: Oct 13, 2022
• Publication Date: Jan 31, 2023
• Deposit Date: Oct 13, 2022
• Publicly Available Date: Oct 13, 2022
• Journal: Chemosphere
• Print ISSN: 0045-6535
• Electronic ISSN: 1879-1298
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 310
• Article Number: 136828
• DOI: https://doi.org/10.1016/j.chemosphere.2022.136828
• Keywords: In-reservoir treatment; Water treatment; Visible light photocatalysis; Graphitic-carbon nitride; Titanium dioxide
• Public URL: https://rgu-repository.worktribe.com/output/1777743
• Additional Information: This article has been published with separate supporting information. This supporting information has been incorporated into a single file on this repository and can be found at the end of this document.