Oxidation of Sulfonamides in Aqueous Solution by UV-TiO2-Fe(VI).
The photocatalytic degradation of sulfonamides in aqueous TiO2 suspension under UV irradiation has been investigated using potassium ferrate as electron acceptors. The results showed that the stability of Fe(VI) is dependent on pH significantly, and the stability reduces obviously in the presence of UV-TiO2. The experiments indicated that Fe(VI) could effectively scavenge the conduction band electrons from the surface of TiO2. The photocatalytic oxidation of sulfonamides with Fe(VI) was found to be much faster than that without Fe(VI). The SD, SM, and SMX concentration was greatly reduced by 89.2%, 83.4%, and 82.0%, respectively, after 10 min with UV-TiO2-Fe(VI), comparing to 65.2%, 66.0%, and 71.9%, respectively, with Fe(VI) only in the dark and 71.3%, 72.7%, and 76.0%, respectively, with UV-TiO2. The pH value of solution significantly influenced the sulfonamides degradation in UV-TiO2-Fe(VI) system. The degradation amount of sulfonamides after 10 min was a maximum at pH 7. The intermediate products of sulfonamides oxidation by UV-TiO2-Fe(VI) were analysed by LC-HESI-MS-MS and the results suggested that a majority of sulfonamides turned into large-molecule products without complete mineralization.
State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China ; Shanghai Urban Water Resources Development and Utilization National Engineering Center Co. Ltd., Shanghai 200082, China.
Yan
Y
Ma
College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China ; Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Zhejiang University, Hangzhou 310058, China.
Kejia
K
Zhang
College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China ; Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Zhejiang University, Hangzhou 310058, China.
Cong
C
Li
College of Civil Engineering and Architecture, Zhejiang University, Hangzhou 310058, China ; Key Laboratory of Drinking Water Safety and Distribution Technology of Zhejiang Province, Zhejiang University, Hangzhou 310058, China.
Tuqiao
T
Zhang
State Key Laboratory of Pollution Control and Resource Reuse, Tongji University, Shanghai 200092, China.
Naiyun
N
Gao
D006863:Hydrogen-Ion Concentration; D007501:Iron / Q000737:chemistry*; D055668:Photochemical Processes; D013449:Sulfonamides / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*; D014466:Ultraviolet Rays; D014867:Water / Q000737:chemistry*
D013449:Sulfonamides; D014867:Water; C009495:titanium dioxide; D014025:Titanium; D007501:Iron