Correlation Engine 2.0
Clear Search sequence regions

Sizes of these terms reflect their relevance to your search.

Photocatalytic remediation technology has been shown to be a favorable approach for the removal of a range of environmental pollutants in water treatment. While this approach can often achieve complete degradation, often overlooked are reaction intermediates that are potentially as harmful as the original parent compound. In the case of photocatalytic oxidation of the herbicide 2-methyl-4-chlorophenoxyacetic acid (MCPA), we have recently shown that 4-chloro-2-methylphenol (CMP) is formed as the primary intermediate. To ensure the continued development of the technology, it is crucial to ensure the removal of both MCPA and CMP can be achieved by photocatalysis. Reported here is the enhanced photocatalytic removal and subsequent suppression of MCPA and CMP respectively, by the addition of small quantities of H2O2. While the addition of H2O2 often accelerates degradation rates (via increased OH radical production), it was found to restrict the formation of CMP in this study through competitive adsorption at the surface of TiO2. Based on the combination of MCPA removal coupled with supressed CMP formation, 0.5% H2O2 was determined to be an optimal loading for the process. Under these conditions 100% MCPA removal was achieved (to the limit of HPLC detection) after 45 min irradiation at a degradation rate of ∼1 mg L-1 min-1 (ƞphoton = 4.4), which also resulted in a ∼83% reduction in CMP formation when compared to a system with no H2O2 present. Crown Copyright © 2021. Published by Elsevier Ltd. All rights reserved.


Jamie Kelly, Cíara McDonnell, Nathan Skillen, Panagiotis Manesiotis, Peter K J Robertson. Enhanced photocatalytic degradation of 2-methyl-4-chlorophenoxyacetic acid (MCPA) by the addition of H2O2. Chemosphere. 2021 Jul;275:130082

Expand section icon Mesh Tags

Expand section icon Substances

PMID: 33677269

View Full Text