Comparison of UV-A photolytic and UV/TiO2 photocatalytic effects on Microcystis aeruginosa PCC7813 and four microcystin analogues: a pilot scale study.

Menezes, Indira; Capelo-Neto, Jos�; Pestana, Carlos J.; Clemente, Allan; Hui, Jianing; Irvine, John T.S.; Gunaratne, H.Q. Nimal; Robertson, Peter K.J.; Edwards, Christine; Gillanders, Ross N.; Turnbull, Graham A.; Lawton, Linda A.

Abstract

To date, the high cost of supplying UV irradiation has prevented the widespread application of UV photolysis and titanium dioxide based photocatalysis in removing undesirable organics in the water treatment sector. To overcome this problem, the use of UV-LEDs (365 nm) for photolysis and heterogeneous photocatalysis applying TiO2 coated glass beads under UV-LED illumination (365 nm) in a pilot scale reactor for the elimination of Microcystis aeruginosa PCC7813 and four microcystin analogues (MC-LR, -LY, -LW, -LF) with a view to deployment in drinking water reservoirs was investigated. UV-A (365 nm) photolysis was shown to be more effective than the UV/TiO2 photocatalytic system for the removal of Microcystis aeruginosa cells and microcystins. During photolysis, cell density significantly decreased over 5 days from an initial concentration of 5.8 × 106 cells mL−1 until few cells were left. Both intra- and extracellular microcystin concentrations were significantly reduced by 100 and 92 %, respectively, by day 5 of the UV treatment for all microcystin analogues. During UV/TiO2 treatment, there was great variability between replicates, making prediction of the effect on cyanobacterial cell and toxin behavior difficult.

Citation

MENEZES, I., CAPELO-NETO, J., PESTANA, C.J., CLEMENTE, A., HUI, J., IRVINE, J.T.S., GUNARATNE, H.Q.N., ROBERTSON, P.K.J., EDWARDS, C., GILLANDERS, R.N., TURNBULL, G.A. and LAWTON, L.A. 2021. Comparison of UV-A photolytic and UV/TiO2 photocatalytic effects on Microcystis aeruginosa PCC7813 and four microcystin analogues: a pilot scale study. Journal of environmental management [online], 298, article 113519. Available from: https://doi.org/10.1016/j.jenvman.2021.113519

• Journal Article Type: Article
• Acceptance Date: Aug 7, 2021
• Online Publication Date: Aug 16, 2021
• Publication Date: Nov 15, 2021
• Deposit Date: Aug 20, 2021
• Publicly Available Date: Aug 17, 2022
• Journal: Journal of environmental management
• Print ISSN: 0301-4797
• Electronic ISSN: 1095-8630
• Publisher: Elsevier
• Peer Reviewed: Peer Reviewed
• Volume: 298
• Article Number: 113519
• DOI: https://doi.org/10.1016/j.jenvman.2021.113519
• Keywords: Blue-green algae; Cyanotoxins; Water treatment; Titanium dioxide; Cyanobacteria
• Public URL: https://rgu-repository.worktribe.com/output/1411601
• Related Public URLs: https://rgu-repository.worktribe.com/output/1411656