Mechanism studies on chlorine and potassium permanganate degradation of microcystin-LR in water using high-performance liquid chromatography tandem mass spectrometry.
The presence of microystins (MCs) in water has the potential to harm people's health. In the MCs various isomers, MC-LR has the strongest toxicity and is the most harmful one. At present, several kinds of pre-oxidants, which are commonly used in water treatment process, are effective to remove MC-LR. However, it is still not clear about their degeneration mechanisms. Chlorine and potassium permanganate were selected in the present work since they are used worldwide for preoxidation treatment. Using the testing method of HPLC-MS, studies on the degeneration of MC-LR were conducted. The results indicate that HPLC-MS is creditable and sensitive. It was also found that linear relationship between concentration of MC-LR and peak area holds in the range of 5-500 microg.L(-1) on the calibration curves, the correlation coefficient (R2) is 0.9993. Under the general condition of oxidant dose and reaction time, MC-LR was degraded rapidly. With active chlorine and potassium permanganate the degradation reaction followed the mode of first-order kinetics. The molecular weight of the degradation product was determined through analyzing the full-scan mass spectrum of MC-LR. And the oxidative degradation mechanism of MC-LR was discussed as well.
Huang
Ting-Lin
TL
Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture & Technology, Xi'an, Shaanxi, China. huangtinglin@xauat.edu.cn
Zhao
Jian-Wei
JW
Chai
Bei-Bei
BB
D017606:Chlorine Compounds / Q000737:chemistry*; D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D007700:Kinetics; D017895:Manganese Compounds / Q000737:chemistry*; D052998:Microcystins / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry*; D011196:Potassium Permanganate / Q000737:chemistry*; D053719:Tandem Mass Spectrometry / Q000379:methods*; D018508:Water Purification / Q000379:methods
D017606:Chlorine Compounds; D017895:Manganese Compounds; D052998:Microcystins; D010087:Oxides; D011196:Potassium Permanganate; C048856:permanganic acid