TY - JOUR
T1 - Mechanisms of photocatalytic degradation of Victoria Blue R using nano-TiO2
AU - Mai, F. D.
AU - Lu, C. S.
AU - Wu, C. W.
AU - Huang, C. H.
AU - Chen, J. Y.
AU - Chen, C. C.
N1 - Funding Information:
This research was supported by the National Science Council of the Republic of China.
PY - 2008/9/1
Y1 - 2008/9/1
N2 - The TiO2-mediated photocatalysis process was used to successfully degrade dye pollutants. To better understand the mechanistic details of this TiO2-assisted photodegradation of the Victoria Blue R (VBR) dye with UV irradiation, forty-four intermediates of the process were separated, identified and characterized by HPLC-PDA-ESI-MS (high performance liquid chromatography-photodiode array-electrospray ionization-mass spectrometry) technique in this study, and their evolution during the photocatalytic reaction is presented. The results indicated that the N-de-alkylation degradation of VBR dye took place in a stepwise manner to yield mono-, di-, tri-, tetra-, penta-, hexa-N-de-methylated and mono-N-de-ethylated VBR species, with N-hydroxyalkylated intermediates generated during the process. Moreover, the oxidative degradation yielded 4-diethylaminophenol, 4-diethylamino-4′-diethylaminobenzophenone, 4-(N,N-dimethylaminophenyl)-4′-(N′-ethylaminonaphthyl)ketone, 4-(N-ethylamino)naphthenol and their N-de-alkylated products. The reaction mechanisms of TiO2/UV proposed in this study should be useful for future application of the technology to the degradation of dyes.
AB - The TiO2-mediated photocatalysis process was used to successfully degrade dye pollutants. To better understand the mechanistic details of this TiO2-assisted photodegradation of the Victoria Blue R (VBR) dye with UV irradiation, forty-four intermediates of the process were separated, identified and characterized by HPLC-PDA-ESI-MS (high performance liquid chromatography-photodiode array-electrospray ionization-mass spectrometry) technique in this study, and their evolution during the photocatalytic reaction is presented. The results indicated that the N-de-alkylation degradation of VBR dye took place in a stepwise manner to yield mono-, di-, tri-, tetra-, penta-, hexa-N-de-methylated and mono-N-de-ethylated VBR species, with N-hydroxyalkylated intermediates generated during the process. Moreover, the oxidative degradation yielded 4-diethylaminophenol, 4-diethylamino-4′-diethylaminobenzophenone, 4-(N,N-dimethylaminophenyl)-4′-(N′-ethylaminonaphthyl)ketone, 4-(N-ethylamino)naphthenol and their N-de-alkylated products. The reaction mechanisms of TiO2/UV proposed in this study should be useful for future application of the technology to the degradation of dyes.
KW - Dye
KW - HPLC-PDA-ESI-MS
KW - Nano-TiO
KW - Photocatalytic
KW - Victoria Blue R
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U2 - 10.1016/j.seppur.2008.02.006
DO - 10.1016/j.seppur.2008.02.006
M3 - Article
AN - SCOPUS:50049102725
SN - 1383-5866
VL - 62
SP - 423
EP - 436
JO - Gas Separation and Purification
JF - Gas Separation and Purification
IS - 2
ER -