[Control on products of NDMA degradation by UV/O3].
Comparison experiments of two advanced oxidation processes, UV/O3 and UV/H2O2, were carried out to evaluate their degradation effect of N-nitrosodimethylamine (NDMA) and controlling effect of dimethylamine (DMA) formation. The results showed that UV/H2O2 could enhance NDMA degradation, but could not control on the formation of DMA. UV/O3 was not only effective for NDMA degradation, but also was good at controlling on DMA formation. Furthermore, factors affecting the formation of DMA during degradation of NDMA by UV/O3 were studied. The formation of DMA decreased with O3 dosage increasing and DMA was 0.98 mg x L(-1) with 7.7 mg x L(-1) NDMA and 6.64 mg x L(-1) O3 dose. Solution pH had obvious effect on controlling of DMA formation during degradation of NDMA by UV/O3 . The formation of DMA lightly increased with pH increasing from acid to neutral but dramatically decreased in basic aqueous solution. The formation of DMA was only 0.3 mg x L(-1) when the initial concentration of NDMA was 7.7 mg x L(-1) under pH = 11.0 condition. UV/O3 had better controlling of DMA formation with lesser initial concentration of NDMA.
Xu
Bing-bing
BB
School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China. xbb_hit@126.com
Chen
Zhong-lin
ZL
Qi
Fei
F
Yang
Lei
L
Huang
Lu-xi
LX
D004123:Dimethylamines / Q000737:chemistry / Q000302:isolation & purification*; D004128:Dimethylnitrosamine / Q000737:chemistry / Q000302:isolation & purification*; D006861:Hydrogen Peroxide / Q000737:chemistry; D010126:Ozone / Q000737:chemistry*; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000302:isolation & purification*; D018508:Water Purification / Q000379:methods
D004123:Dimethylamines; D014874:Water Pollutants, Chemical; D010126:Ozone; C034516:dimethylamine; D006861:Hydrogen Peroxide; D004128:Dimethylnitrosamine