Photocatalytic degradation of microcystin-LR and anatoxin-a with presence of natural organic matter using UV-light emitting diodes/TiO2 process

Boram Yang, Hee Deung Park, Seok Won Hong, Sang Hyup Lee, Jeong Ann Park, Jae Woo Choi

Research output: Contribution to journalArticle

Abstract

Cyanotoxins are released into water bodies when cyanobacterial blooms occur. Representative cyanotoxins are microcystin-LR (MC-LR), which is one of the most-frequently detected, and anatoxin-a (ANTX), threatening human health through the liver damage and nervous system, respectively. One of the advanced oxidation processes, UV/TiO2 process is effective for MC-LR degradation; however, applying conventional UV lamps is an ongoing issue owing to disadvantages, such as use of mercury and high energy consumption. To resolve these, this study aims to use light emitting diodes (LEDs), developed by the Lumens Co., combined with commercial TiO2 for the removal of two types of cyanotoxins, MC-LR and ANTX. With 0.05 g L−1 of TiO2, over 99.9 % of the MC-LR was degraded in 15 min. Under acidic conditions, MC-LR and TiO2 were converted into MC-LRH and TiO2 +, then, electrostatic attraction was generated between them. Therefore, the degradation rate constant (k) of MC-LR was higher under acidic conditions than neutral or basic conditions. The natural organic matter (NOM) served as a scavenger of O[rad]H, reducing the MC-LR degradation rate under UV-LED/TiO2 process. 35%–53.6% degradation of NOM due to the decrease in humic substances and building blocks, and the increase in low molecular weight neutrals and low molecular weight acids. The degradation efficiency of MC-LR was higher than that of ANTX, and both cyanotoxins were completely degraded within 15 min. The k of MC-LR and ANTX were similar but significantly reduced due to the NOM and alkalinity of the water collected from the Han River.

Original languageEnglish
Article number101163
JournalJournal of Water Process Engineering
Volume34
DOIs
Publication statusPublished - 2020 Apr

Keywords

  • Anatoxin-A
  • Microcystin-LR
  • Natural organic matter
  • TiO
  • UV-LEDs

ASJC Scopus subject areas

  • Biotechnology
  • Safety, Risk, Reliability and Quality
  • Waste Management and Disposal
  • Process Chemistry and Technology

Fingerprint Dive into the research topics of 'Photocatalytic degradation of microcystin-LR and anatoxin-a with presence of natural organic matter using UV-light emitting diodes/TiO<sub>2</sub> process'. Together they form a unique fingerprint.

  • Cite this