Effects of colloidal TiO2 particles on photodegradation of dissolved organic matter from different sources: Based on molecular weight difference analysis

被引：0
作者：
Li F. [1 ,2 ]
Xu H. [1 ]
Jiang H. [1 ]
机构：
[1] State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing
[2] University of Chinese Academy of Sciences, Beijing
来源：
Hupo Kexue/Journal of Lake Sciences | 2021年 / 33卷 / 04期
关键词：
Colloidal TiO[!sub]2[!/sub] particles; Dissolved organic matter (DOM); Molecular weight distribution; Photodegradation; Ultrafiltration;
D O I：
10.18307/2021.0417
中图分类号：
学科分类号：
摘要：
Dissolved organic matter (DOM) exists widely in water environmental media, and its photodegradation process significantly affects the chemical species and ecological risk of pollutants in waters. This study took the typical terrestrial natural organic matter (NOM) and algal-derived organic matter (AlgOM) as the research objects, fractionating the initial DOM sample (Bulk, <0.45 μm) into high molecular weight (HMW, 1 kDa-0.45 μm) and low molecular weight (LMW, <1 kDa) fractions via tangential ultrafiltration technique, to analyze the difference of photodegradation behavior of organic components with different molecular weights in the presence of colloidal TiO2 particles. The characterization results showed that organic matter of DOM samples was relatively more distributed in LMW components (55.3%-57.8%), but HMW was more aromatic than LMW components. Three-dimensional fluorescence spectrum showed that AlgOM was rich in protein-like and humus-like substances, while NOM only contained humus-like substances. Further analysis revealed that protein-like substances were mainly distributed in HMW components, and humus-like substances were mainly distributed in LMW components. The presence of colloidal particles promoted the photodegradation of organic matter and aromatic substances in NOM by catalytic effect, while inhibited the photodegradation of organic matter and aromatic substances in AlgOM by adsorption effect. Colloidal particles did not change the photodegradation efficiency order of organic matter in DOM with different molecular weights, all of which were HMW>Bulk>LMW, indicating that HMW organic matters were easier to be photodegraded. However, without colloidal particles, the photodegradation efficiency of AlgOM and NOM aromatics was LMW>Bulk>HMW, and the presence of colloidal particles changed the photodegradation order of NOM aromatics with different molecular weights. In addition, terrestrial humus was more easily degraded than algal humus in the absence of colloidal particles, and the presence of colloidal particles promoted the photodegradation of both algal and terrestrial humus. Compared with HMW humus, LMW humus had higher photosensitivity and preferential degradation characteristics. © 2021 by Journal of Lake Sciences.
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页码：1163 / 1174
页数：11
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  • [1] Chin WC, Orellana MV, Verdugo P., Spontaneous assembly of marine dissolved organic matter into polymer gels, Nature, 391, 6667, pp. 568-572, (1998)
  • [2] He W, Bai ZL, Li YL, Et al., Advances in the characteristics analysis and source identification of the dissolved organic matter, Acta Scientiae Circumstantiae, 36, 2, pp. 359-372, (2016)
  • [3] Hosen JD, Aho KS, Fair JH, Et al., Source switching maintains dissolved organic matter chemostasis across discharge levels in a large temperate river network, Ecosystems, pp. 1-21, (2020)
  • [4] Wang WW, Zheng BH, Jiang X, Et al., Characteristics and source of dissolved organic matter in lake Hulun, A large shallow eutrophic steppe lake in Northern China, Water, 12, 4, (2020)
  • [5] Ducklow HW, Hansell DA, Morgan JA., Dissolved organic carbon and nitrogen in the Western Black Sea, Marine Chemistry, 105, 1, pp. 140-150, (2007)
  • [6] Shafiquzzaman M, Haider H, Bhuiyan MA, Et al., Spatiotemporal variations of DOM components in the Kushiro River impacted by a wetland, Environmental Science and Pollution Research, 27, 15, pp. 18287-18302, (2020)
  • [7] Yu HB, Song YH, Gao HJ, Et al., Applying fluorescence spectroscopy and multivariable analysis to characterize structural composition of dissolved organic matter and its correlation with water quality in an urban river, Environmental Earth Sciences, 73, 9, pp. 5163-5171, (2015)
  • [8] Yan YW, Zhai HY, Wang XJ., Formation characteristics of disinfection by-products from algal organic matter in ozonation/chlorine disinfection, China Water & Wastewater, 36, 5, pp. 7-13, (2020)
  • [9] Wu DM, Li QF, Wu CY., Adsorption of dissolved organic matter onferrallitic soils, Environmental Chemistry, 35, 4, pp. 639-650, (2016)
  • [10] Hu B, Wang PF, Bao TL, Et al., The photochemical release of dissolved organic matter from resuspended sediments: Insights from fluorescence spectroscopy, Chemosphere, 257, (2020)
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