Degradation of different fractions of natural organic matter in drinking water by the UV/persulfate process.
Environ Sci Pollut Res Int
; 31(43): 55636-55647, 2024 Sep.
Article
in En
| MEDLINE
| ID: mdl-39240438
ABSTRACT
The existence of natural organic matter (NOM) causes many problems in drinking water treatment processes. The degradation of different fractions of NOM in drinking water was studied using the ultraviolet/persulfate (UV/PS) process. The NOM was separated into hydrophobic (HPO), transition hydrophilic (TPI) and hydrophilic (HPI) fractions by reverse osmosis and XAD series resins. The effects of degradation were evaluated by dissolved organic carbon (DOC), UV254, three-dimensional fluorescence-parallel factor analysis (EEM-PARAFAC), and trihalomethane formation potential (THMFP). The results showed that UV/PS process could remove the three fractions of DOC, UV254, as well as the fluorescent components humic acid-like (C1 and C2) and protein-like (C3). The maximum removal rates of DOC of HPO, TPI, and HPI fractions were 34.6%, 38.4%, and 73.9%, respectively, and the maximum removal rates of UV254 were 72.1%, 86.3%, and 86.8%, respectively. The removal rate of the three fluorescent components can reach 100%, and C3 is easier to remove than C1 and C2 under the low PS dosage conditions. The order of kinetic degradation rate constant of UV254 first-order reaction is HPI > TPI > HPO. The optimum pH conditions for the degradation of HPO, TPI, and HPI fractions were acidic, basic, and neutral, respectively. The specific THMFP of HPO was higher than that of TPI and HPI. The specific THMFP of HPO and TPI fractions increased with the increase of radiation time, while the HPI fraction showed the opposite trend. THMFP has different degrees of correlation with DOC, UV254, C1, and C2. This study can provide a theoretical basis for the selection of the UV/PS process for drinking water sources containing NOM with different characteristics.
Key words
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Ultraviolet Rays
/
Water Pollutants, Chemical
/
Drinking Water
/
Water Purification
Language:
En
Journal:
Environ Sci Pollut Res Int
Journal subject:
SAUDE AMBIENTAL
/
TOXICOLOGIA
Year:
2024
Document type:
Article
Affiliation country:
Country of publication: