|
Effect of Fe (Ⅲ)on the photochemical activity of dissolved organic matter from different sources |
Received:April 16, 2019 |
View Full Text View/Add Comment Download reader |
KeyWord:dissolved organic matter (DOM);Fe (Ⅲ);photochemical activity;reactive species |
Author Name | Affiliation | E-mail | LIU Yan-hong | College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China National Positioning Observation Station of Hungtse Lake Wetland Ecosystem in Jiangsu Province, Hongze 223100, China | | LI Wei | College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China National Positioning Observation Station of Hungtse Lake Wetland Ecosystem in Jiangsu Province, Hongze 223100, China | uwliwei@163.com | HAN Jian-gang | College of Biology and the Environment, Nanjing Forestry University, Nanjing 210037, China Co-Innovation Center for the Sustainable Forestry in Southern China, Nanjing Forestry University, Nanjing 210037, China National Positioning Observation Station of Hungtse Lake Wetland Ecosystem in Jiangsu Province, Hongze 223100, China | hanjiangang76@126.com |
|
Hits: 1797 |
Download times: 1521 |
Abstract: |
To study the effects of Fe(Ⅲ),which commonly occurs in aquatic environments, on the photochemical activity of dissolved organic matter(DOM), furfuryl alcohol(FFA), 4-chlorobenzoic acid(pCBA), and 2,4,6-trimethylphenol(TMP) were employed as molecular probes for 1O2,·OH, and 3DOM*.This was done to study the effects of Fe(Ⅲ) on the steady state concentration of 1O2 and·OH generated and the degradation reaction rate of TMP caused by the photosensitizer of DOM under different light sources and pH conditions. The results showed that the ability of DOM to produce reactive species under the irradiation of a mercury lamp was significantly higher than that under a xenon lamp, indicating that more reactive species were produced at a higher light intensity. Under different light sources and pH conditions, the ability of DOM to produce reactive species differed. Overall, Suwannee River humic acid(SRHA) and Suwannee River natural organic matter(SRNOM) had better 1O2 and·OH generation capabilities, while effluent organic matter(EfOM) had higher 3DOM* generation capabilities. A low concentration of Fe(Ⅲ) (10 μmol·L-1) had no significant impact on the photochemical reactivity of DOM, while a high concentration of Fe(Ⅲ) (25~50 μmol·L-1) inhibited DOM from producing reactive species, and the inhibitory effect was enhanced with the increase of the Fe(Ⅲ) concentration. The E2/E3 value of the DOM solution decreased with the increase of the Fe(Ⅲ) concentration, which showed a positive correlation with the steady state concentration of 1O2 and·OH and the photodegradation rate constant of TMP caused by a single DOM and Fe system. In real aquatic environments, the presence of Fe(Ⅲ) may inhibit the photochemical reactivity of DOM, inhibiting the photochemical transformation of organic pollutants, eventually causing a higher ecotoxicology risk. |
|
|
|