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ABSTRACT: Perchlorate is widely known as an inorganic endocrine disruptor. In this study, MgAl-CO3 layered double hydroxides with different Mg/Al molar ratios were prepared using a coprecipitation method and followed by a calcination process at a temperature range of 300 to 700 degrees C. Results showed that the best synthesis conditions were a calcination temperature of 550 degrees C and Mg/Al molar ratio of 3. Further, the adsorbent and its adsorption product were characterized by x-ray diffraction, Fourier transform-infrared spectroscopy, and thermogravimetric-differential thermal analysis. The layered double hydroxides structures in the adsorbent were lost during calcination at 550 degrees C but were reconstructed subsequent to adsorption of perchlorate, indicating that the "memory effect" appeared to play an important role in perchlorate adsorption. The perchlorate adsorption pattern was best described by the pseudo-second-order kinetics model, while the Freundlich isotherms appropriately explained perchlorate adsorption data.
Water Environment Research 04/2013; 85(4):331-9. · 0.88 Impact Factor
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ABSTRACT: Disinfection by-products (DBPs) are a great challenge to our drinking water security. Particularly, nitrosamines (NAms), as emerging DBPs, are potently carcinogenic, mutagenic, and teratogenic, and have increasingly attained public attention. This study was to evaluate the performance of the NAms degradation by the ultraviolet (UV) irradiation (253.7 nm) in the presence of hydrogen peroxide (H(2)O(2)). In the UV/H(2)O(2) system, hydroxyl radicals (OH), a type of nonselective and powerful oxidant, was produced to attack the molecules of NAms. Factors affecting the treatment efficiency, including the H(2)O(2) dosage, initial NAms concentration, UV irradiation intensity, initial solution pH, and inorganic anions present in water, were evaluated. All the NAms degradation exhibited a pseudo-first-order kinetics pattern. Within 60 min, 0.1 mg/L of any NAms could be almost decomposed except NDPhA that required 120 min for complete removal, at 25 μmol/L H(2)O(2) and at initial pH 7. Results demonstrate that the UV/H(2)O(2) treatment is a viable option to control NAms in water.
Journal of hazardous materials 06/2012; 231-232:43-8. · 4.14 Impact Factor
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ABSTRACT: A novel photocatalytic reactor was developed to remove (1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane) (DDT) from water. In
the reactor, a cenosphere was used to support TiO2 film made by means of sol-gel. Because the cenospheres were coated with TiO2, their specific gravity was slightly increased from the original 0.6∼0.8 to 0.8∼0.9, so that they were able to be suspended
in water. With the mixed operation of a bubbler, the water in the reactor was in a well-fluidized state. The bottom of the
reactor is a sand filter bed, which can be used to prevent the photocatalyst from being lost. A mathematical model of the
reactor has been developed in the two primary influential factors: ultraviolet (UV) light intensity and photocatalyst concentration.
With such a model, the reactor can be designed more reasonably.
Journal of Zhejiang University - Science A: Applied Physics & Engineering 04/2012; 10(5):732-738. · 0.41 Impact Factor
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ABSTRACT: The immediate and long-term impacts of potassium permanganate (KMnO(4)) as pre-oxidant on Microcystis aeruginosa and microcystin-LR (MC-LR) release risk were investigated. The cell density and the integrity of M. aeruginosa were determined by a flow cytometry, and typical photosynthetic parameters were measured by a pulse amplitude modulated fluorometer. The photosynthetic parameters were reduced to different degrees, accompanied with slight cytoclasis and complete degradation of extracellular MC-LR immediately after various dosages KMnO(4) oxidation (2-20 mg L(-1)). In a 6-d cultivation following 5 mg L(-1) KMnO(4) oxidation, the cell density decreased from 3.9×10(6) to 0.6×10(6) cells mL(-1), and then increased to 0.9×10(6) cells mL(-1), while the extracellular MC-LR increased from 0 to 51.2 μg L(-1). In the cultivation after 10 mg L(-1) KMnO(4) treatment, the intracellular MC-LR and cell activity significantly declined, while significant cytoclasis (cell density from 3.8×10(6) to 0 cells mL(-1)) and MC-LR release (increase from 0 to 15.2 μg L(-1)) were observed. The photosynthetic parameters were found to be useful tools to predict the recovery tendency of M. aeruginosa cells, and the MC-LR release risk should be considered during KMnO(4) pre-oxidation in water-treatment plants.
Journal of hazardous materials 04/2012; 219-220:267-75. · 4.14 Impact Factor
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ABSTRACT: Pilot-scale tests were performed to reduce the formation of several nitrogenous and carbonaceous disinfection by-products (DBPs) with an integrated ozone and biological activated carbon (O(3)-BAC) treatment process following conventional water treatment processes (coagulation-sedimentation-filtration). Relative to the conventional processes alone, O(3)-BAC significantly improved the removal of turbidity, dissolved organic carbon, UV(254), NH(4)(+) and dissolved organic nitrogen from 98-99%, 58-72%, 31-53%, 16-93% and 35-74%, respectively, and enhanced the removal efficiency of the precursors for the measured DBPs. The conventional process was almost ineffective in removing the precursors of trichloronitromethane (TCNM) and dichloroacetamide (DCAcAm). Ozonation could not substantially reduce the formation of DCAcAm, and actually increased the formation potential of TCNM; it chemically altered the molecular structures of the precursors and increased the biodegradability of N-containing organic compounds. Consequently, the subsequent BAC filtration substantially reduced the formation of the both TCNM and DCAcAm, thus highlighting a synergistic effect of O(3) and BAC. Additionally, O(3)-BAC was effective at controlling the formation of the total organic halogen, which can be considered as an indicator of the formation of unidentified DBPs.
Chemosphere 12/2011; 86(11):1087-91. · 3.21 Impact Factor
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ABSTRACT: Algae organic matters (AOM), including intracellular organic matters (IOM) and extracellular organic matters (EOM), are causing numerous water quality issues, among which formation of disinfection byproducts (DBPs) and odor & taste (O&T) compounds are of particular concern. In this study, physiochemical properties of IOM and EOM of Microcystic aeruginosa under an exponential growth phase (2.01×10(11)/L) were comprehensively characterized. Moreover, the yields of DBPs during AOM disinfection and O&T-causing compounds were quantified. Hydrophilic organic matters accounted for 86% and 63% of DOC in IOM and EOM, respectively. Molecular weight (MW) fractions of IOM in <1 kDa, 40-800 kDa, and >800 kDa were 27%, 42%, and 31% of DOC, respectively, while EOM primarily contained 1-100 kDa molecules. Besides, a low SUVA (0.84 L/mg m) and the specific fluorescence spectra suggested that AOM (especially IOM) was principally comprised of protein-like substances, instead of humic-like matters. The formation potentials of chloroform, chloroacetic acid, and nitrosodimethylamine were 21.46, 68.29 and 0.0096 μg/mg C for IOM, and 32.44, 54.58 and 0.0189 μg/mg C for EOM, respectively. Furthermore, the dominant O&T compound produced from EOM and IOM were 2-MIB (68.75 ng/mg C) and β-cyclocitral (367.59 ng/mg C), respectively. Of note, dimethyltrisulfide became the prevailing O & T compound following anaerobic cultivation.
Water Research 12/2011; 46(4):1233-40. · 4.86 Impact Factor
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ABSTRACT: In this study, the immediate and long-term impacts of shortwave ultraviolet (UV-C) irradiation on photosynthetic capacity, survival, and recovery of Microcystis aeruginosa were investigated. The risk of microcystin-LR (MC-LR) release during irradiation was also estimated. The cell density was determined by a flow cytometry, and typical chlorophyll fluorescence parameters, including the effective quantum yield, photosynthetic efficiency and maximal electron transport rate, were measured by a pulse amplitude modulated (PAM) fluorometer. Under various UV-C dosages (140-4200 mJ cm(-2)), photosynthetic capacities were reduced, to different degrees, accompanied by slight cytoclasis and complete degradation of extracellular MC-LR immediately after irradiation. In a 6-d cultivation following UV-C irradiation, cell density and extracellular MC-LR in the samples treated by 140 mJ cm(-2) UV-C irradiation increased from 4.0×10(6) cells mL(-1) and 8 μg L(-1) to 5.1×10(6) cells mL(-1) and 20 μg L(-1), respectively. Significant M. aeruginosa cytoclasis (cell density from 4.0×10(6) to 1.0×10(6) cells mL(-1)) and MC-LR release (2-25 μg L(-1)) occurred when the UV-C dosage reached 350 mJ cm(-2). Cell cytoclasis and MC-LR release were enhanced in the cultivated samples under higher UV-C dosages. Results revealed that photosynthetic parameters were useful tools to predict the recovery profiles of M. aeruginosa cells, and the MC-LR release risk should be considered after UV-C inactivation.
Water Research 12/2011; 46(4):1241-50. · 4.86 Impact Factor
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ABSTRACT: The formation of disinfection by-products (DBPs), including both nitrogenous DBPs (N-DBPs) and carbonaceous DBPs (C-DBPs), was investigated by analyzing chlorinated water samples following the application of three pretreatment processes: (i) powdered activated carbon (PAC) adsorption; (ii) KMnO(4) oxidation and (iii) biological contact oxidation (BCO), coupled with conventional water treatment processes. PAC adsorption can remove effectively the precursors of chloroform (42.7%), dichloroacetonitrile (28.6%), dichloroacetamide (DCAcAm) (27.2%) and trichloronitromethane (35.7%), which were higher than that pretreated by KMnO(4) oxidation and/or BCO process. The removal efficiency of dissolved organic carbon by BCO process (76.5%)--was superior to that by PAC adsorption (69.9%) and KMnO(4) oxidation (61.4%). However, BCO increased the dissolved organic nitrogen (DON) concentration which caused more N-DBPs to be formed during subsequent chlorination. Soluble microbial products including numerous DON compounds were produced in the BCO process and were observed to play an essential role in the formation of DCAcAm in particular.
Bioresource technology 12/2011; 102(24):11161-6. · 4.25 Impact Factor
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ABSTRACT: In this study, the mechanisms and factors affecting the inactivation and degradation efficiency during UV-C irradiation of Microcystis aeruginosa, a harmful cyanobacteria strain, were investigated. Under different experimental conditions, the concentrations of three bioactivity materials, including protein, phycocyanin and chl-a, were measured, and fluorescence regional integration (FRI) was used to quantify the results of excitation emission matrix fluorescence spectroscopy. Furthermore, any alternation occurring in cell ultrastructure was determined using transmission electron microscopy. Results showed that UV-C could effectively damage the M.aeruginosa cells, most likely via a 3-step procedure, including impairment of photosynthesis system, decomposition of cytoplasmic inclusions, and cell cytoclasis. Comparison of FRI values and biochemical parameters in the presence of H(2)O(2) and HCO(3)(-) under the UV-C irradiation revealed the importance of photolysis and reactive oxygen species (ROS)-induced oxidation. UV-C/H(2)O(2) treatment was more efficient due to enhanced ROS generation, while adding HCO(3)(-) inhibited the ROS-induced oxidation, resulting in suppression on reaction. Humic acid and NO(3)(-), two common water solutes, somewhat inhibited the inactivation and degradation processes, due to the ROS scavenging and "inner filter" effect.
Chemosphere 08/2011; 85(7):1192-8. · 3.21 Impact Factor
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ABSTRACT: A sampling survey investigated the formation of nitrogenous disinfection by-products (N-DBPs) and carbonaceous DBPs (C-DBPs) from pre-chloramination, an increasingly common treatment strategy in China for regulated C-DBP control, followed by subsequent conventional water treatment processes, i.e., coagulation, sedimentation, and filtration. Dihalogenated N-DBPs typically peaked in the summer and early autumn with a relatively higher temperature, with the maximum levels of dichloroacetamide (DCAcAm), dichloroacetonitrile (DCAN), bromochloroacetonitrile, dibromoacetonitrile and dichloroacetone at 1.8, 6.3, 6.0, 2.6 and 1.8μgL(-1) in the finished water, respectively. Also, the levels of all the dichlorinated N-DBPs were correlated with the ratio of dissolved organic nitrogen (DON) to dissolved organic carbon, implying autochthonous DON played an essential role in the formation of these DBPs. In contrast, the yields of trihalogenated DBPs [chloroform (CF), trichloronitromethane (TCNM) and trichloroacetone (TCAce)] appeared not to be significantly affected by seasons. CF and DCAN were the dominant species in trihalomethanes (THMs) and dihaloacetonitriles (DHANs), respectively. Bromine was more readily incorporated into DHANs to form brominated DBPs than THMs during pre-chloramination. Although pre-chloramination can ensure the finished water to meet with the current Chinese THM regulatory limits, the increased levels of TCNM and TCAce may be a new water quality concern.
Chemosphere 08/2011; 85(7):1187-91. · 3.21 Impact Factor
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ABSTRACT: In this study, granular activated carbon (GAC) coated with cetyltrimethyl ammonium bromide (CTAB) (GAC-CTAB) was synthesized to remove perchlorate from water via adsorption. Laboratory-scale batch experiments were performed to study the factors affecting the perchlorate adsorption by GAC-CTAB, including the CTAB content and solution pH, and explore the mechanisms behind the adsorption phenomenon. The novel GAC-CTAB material was characterized by scanning electron microscopy (SEM), zeta potential measurement and Brunauer-Emmett-Teller (BET) analysis. The characterization tests showed that CTAB was deposited on the GAC surface, pH(pzc) of the material was between 2.0 and 3.0, and the BET specific surface area was reduced from 925 to 729 m(2)/g with the increasing CTAB content from 0 to 0.034 mmol CTAB/g GAC. The adsorption process was better described by a pseudo-second-order kinetics model and the Freundlich adsorption model. The CTAB content and solution pH significantly influenced the kinetics and chemical equilibrium of the adsorption. When the CTAB content was increased from 0.0.023 to 0.135 mmol CTAB/g GAC, the K in the Freundlich adsorption isotherm increased from 0.071 to 0.19 mmol/g. The optimal adsorption typically occurred at pH 2-3, close to the pH(pzc) of the solution. Finally, the mechanisms for the adsorption of perchlorate on GAC-CTAB were associated with surface complexation, electrostatic interaction and ion exchange.
Journal of Colloid and Interface Science 03/2011; 357(2):474-9. · 3.07 Impact Factor
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ABSTRACT: This study investigated the degradation of bisphenol-A (BPA) by ultrasonic irradiation in the presence of different additives (H2O2, air bubbles and humic acid) under various operating conditions, i.e., ultrasonic frequency, power intensity and power density. The results demonstrated that the BPA degradation followed pseudo first-order kinetics under different experimental conditions. The optimum power intensities were 0.9, 1.8, and 3.0 W/cm2 at the frequencies of 400, 670, and 800 kHz, respectively. At the fixed frequency (800 kHz), the degradation rate of BPA was shown proportional to the increase of power density applied. With this manner, the BPA sonolysis could be facilitated at H2O2 dosage being lower than 0.1 mmol/L; while BPA degradation was hindered at H2O2 concentration in excess of 1 mmol/L. Additionally, BPA removal was shown to be inhibited by the presence of aeration and humic acid during ultrasonic irradiation. The present study suggested that the degradation rate of BPA assisted by ultrasonic irradiation was influenced by a variety of factors, and high BPA removal rate could be achieved under appropriate conditions.
Journal of Environmental Sciences 01/2011; 23(1):31-6. · 1.66 Impact Factor
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ABSTRACT: Haloacetamides (HAcAms) are an emerging class of nitrogenous disinfection byproducts (N-DBPs). However, there is a limited understanding about the precursors of HAcAms. In this study, we screened the precursors of dichloroacetamide (DCAcAm), the most commonly identified HAcAm in chlorinated or chloraminated drinking water. DCAcAm formation potential (FP) of raw water samples collected in different months from a reservoir in China was determined during chlorination, and the highest DCAcAm FP typically occurred in the summer samples. Dissolved organic matter (DOM) in a representative summer raw water sample was separated into six fractions by a series of resin elutions. Among them, hydrophilic acid (HiA) DOM showed the maximum DCAcAm FP, followed by hydrophilic bases (HiB) and, to a much lower extent, hydrophobic acids (HoA). Fluorescence excitation-emission matrix (EEM) spectra revealed that a mass of protein-like substances in the HiA fraction, made up of amino acids (AAs), were the likely DCAcAm precursors. Finally, we investigated the DCAcAm yields of 20 AAs during chlorination. Among them, seven AAs (aspartic acid, histidine, tyrosine, tryptophan, glutamine, asparagine, phenylalanine) could form DCAcAm during chlorination, with the corresponding DCAcAm yields of 0.231, 0.189, 0.153, 0.104, 0.078, 0.058, and 0.050 mmol/mol AA.
Environmental Science and Technology 05/2010; 44(10):3908-12. · 5.23 Impact Factor
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ABSTRACT: Ultrasonic degradation of parathion has been investigated in this study. At a neutral condition, 99.7% of 2.9 microM parathion could be decomposed within 30 min under 600 kHz ultrasonic irradiation at ultrasonic intensity of 0.69 W/cm(2). The degradation rate increased proportionally with the increasing ultrasonic intensity from 0.10 to 0.69 W/cm(2). The parathion degradation was enhanced in the presence of dissolved oxygen due to formation of more ()OH, but was inhibited in the presence of nitrogen gas owning to the free radical scavenging effect in vapor phase within the cavitational bubbles. CO(3)(2-), HCO(3)(-), and Cl(-) exhibited the inhibiting effects on parathion degradation, and their inhibition degrees followed the order of CO(3)(2-)>HCO(3)(-)>Cl(-). But Br(-) had a promoting effect on parathion degradation, and the effect increased with the increasing Br(-) level. Moreover, both the hydrophobic and hydrophilic natural organic matters (NOM) could slow the parathion degradation, but the inhibiting effect caused by hydrophobic component was greater, especially the strongly hydrophobic NOM. The three reaction pathways of parathion sonolysis were proposed, including formation of paraoxon, formation of 4-nitrophenol, and unknown species products. The kinetics tests showed that anyone of these pathways could not be overlooked, and the fractions of the parathion decomposed in the three pathways were 28.19%, 32.92% and 38.89%, respectively. In addition, 66.61% of paraoxon produced was degraded into 4-nitrophenol. Finally, kinetics models were established to adequately predict the concentrations of parathion, paraoxon and 4-nitrophenol as a function of time.
Ultrasonics Sonochemistry 02/2010; 17(5):802-9. · 3.57 Impact Factor
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ABSTRACT: Synthesis and use of the iron compounds supported on granular activated carbon (ICs/GAC) have shown significant environmental implications for perchlorate (ClO4-) removal. ICs/GAC was synthesized via hydrolyzing FeSO4 x 7H2O on GAC, reduced by NaBH4 solution in polyethylene glycol 6000 and ethanol solution, dried in vacuum condition and exposed to air. Synthesized ICs/GAC was characterized using transmission electron micrograph (TEM), Brunauer-Emmett-Teller, X-ray photoelectron spectroscopy (XPS). ICs/GAC was determined to be containing a large amount of FeOHSO4, Fe2O3 and a small amount of zero-valent iron (ZVI) nanoparticles according to TEM and XPS measurements. Batch static kinetic tests showed that 97% of ClO4- was removed within 10 hr at 90 degrees C and 86% of ClO4- was removed within 12 hr at 25 degrees C, at ICs/GAC dosage of 20 g/L. The experimental results also showed that FeOHSO4 and Fe2O3 nanoparticles have the function of perchlorate adsorption and play important roles in ClO4- removal. The activation energy (E(a)) was determined to be 9.56 kJ/mol.
Journal of Environmental Sciences 01/2010; 22(11):1807-13. · 1.66 Impact Factor
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ABSTRACT: Currently, dissolved nitrogenous organic matters in water, important precursors of disinfection by-products (DBPs), are of significant concern. This study was to explore the formation of chloroform (CF) during chlorination of alanine (Ala), an important nitrogenous organic compound commonly present in water sources. Our results indicated that the CF yield reached a maximum value of 0.143% at the molar ratio of chlorine atom to nitrogen atom (Cl/N)=1.0 over a Cl/N range of 0.2-5.0 (pH=7.0, reaction time=5d, and initial Ala=0.1mM). At an acidic-neutral condition (pH 4-7), the formation of CF was suppressed. However, the highest CF yield (0.227%) occurred at weakly alkaline condition (pH 8.0) (initial Ala=0.1mM, and Cl/N=1.0). The increase of Br(-) in water can increase total trihalomethanes (THMs) and bromo-THMs. However, the bromo-THMs level reached a plateau at Br(-)/Cl>0.04. Finally, based on the computation of frontier electron density and identification and measurement of key intermediates during Ala chlorination, we proposed a formation pathway of CF from Ala chlorination: Ala-->monochloro-N-alanine (MC-N-Ala)-->acetaldehyde (AAld)-->monochloroacetaldehyde acetaldehyde (MCAld)-->dichloroacetaldehyde (DCAld)-->trichloroacetaldehyde (TCAld)-->CF.
Chemosphere 10/2009; 77(10):1346-51. · 3.21 Impact Factor
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ABSTRACT: The stability of haloacetamides (HAcAms) such as dichloroacetamide (DCAcAm) and trichloroacetamide (TCAcAm) was studied under different experimental conditions. The yield of HAcAms during aspartic acid (Asp) chlorination was measured at different molar ratio of chlorine atom to nitrogen atom (Cl/N), pH and dissolved organic carbon (DOC) mainly consisted of humic acid (HA) mixture. Ascorbic acid showed a better capacity to prevent the decay of DCAcAm and TCAcAm than the other two dechlorinating agents, thiosulfate and sodium sulfite. Lower Cl/N favored the DCAcAm formation, implying that breakpoint chlorination might minimize its generation. The pH decrease could lower the concentration of DCAcAm but favored dichloroacetonitrile (DCAN) formation. DCAcAm yield was sensitive to the DOC due to higher chlorine consumption caused by HA mixture. Two possible pathways of DCAcAm formation during Asp chlorination were proposed. Asp was an important precursor of DCAN, DCAcAm and dichloroacetic acid (DCAA), and thus removal of Asp before disinfection may be a method to prevent the formation of DCAcAm, DCAN and DCAA.
Journal of hazardous materials 08/2009; 173(1-3):82-6. · 4.14 Impact Factor
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ABSTRACT: During ultraviolet light (UV) disinfection, nitrate (NO3-) present in raw water may transform to nitrite (NO2-) that can cause serious human diseases. In this study, the formation of NO2- from NO3- was studied at different experimental conditions under the irradiation of a low-pressure ultraviolet (LPUV) lamp at 253.9 nm. The investigated experimental variables included initial NO3- concentration, solution pH (6.2-9.5), and hydrogen peroxide (H2O2) dose (0-25 mg L(-1)). Moreover, the effect of titanium dioxide (TiO2) was determined. Results showed that the formation of NO2- was enhanced at a high initial NO3- concentration and a high pH, but was inhibited, to some different degrees, by introduction of H2O2 or photocatalyst TiO2. The effect of pH on NO2- formation was probably due to the impact of hydrogen ion on the stability of several intermediates such as peroxynitrite (ONOO-), N2O3, and N2O4. And the inhibiting effects of H2O2 and TiO2 were attributable to production of additional hydroxyl radical (OH) that scavenged NO2-. At pH 9.5 and an initial NO3- concentration of 10 mg L(-1) NO3--N, the concentration of NO2- produced was above 0.1 mg L(-1) NO2--N, the Germany drinking water standard. When 25 mg L(-1) H2O2 was added, the NO2- level was decreased below the standard.
Water Science & Technology 01/2009; 60(6):1393-400. · 1.12 Impact Factor
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ABSTRACT: The degradation of Microcystin-LR (MC-LR) in water by hydrogen peroxide assisted ultraviolet (UV/H 2 O 2) process was investigated in this paper. The UV/H 2 O 2 process appeared to be effective in removal of the MC-LR. MC-LR decomposition was primarily ascribed to production of strong and nonselective oxidant-hydroxyl radicals within the system. The intensity of UV radiation, initial concentration of MC-LR, MC-LR purity, dosages of H 2 O 2 , the initial solution pH, and anions present in water, to some extent, influenced the degradation rate of MC-LR. A modified pseudo-first-order kinetic model was developed to predict the removal efficiency under different experimental conditions.
Journal of Zhejiang University - Science A: Applied Physics & Engineering 01/2009; 10:1660-1669. · 0.41 Impact Factor
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ABSTRACT: The degradation of Microcystin-LR (MC-LR) in water by hydrogen peroxide assisted ultraviolet (UV/H 2 O 2) process was investigated in this paper. The UV/H 2 O 2 process appeared to be effective in removal of the MC-LR. MC-LR decomposition was primarily ascribed to production of strong and nonselective oxidant-hydroxyl radicals within the system. The intensity of UV radiation, initial concentration of MC-LR, MC-LR purity, dosages of H 2 O 2 , the initial solution pH, and anions present in water, to some extent, influenced the degradation rate of MC-LR. A modified pseudo-first-order kinetic model was developed to predict the removal efficiency under different experimental conditions.
J Zhejiang Univ Sci A. 01/2009; 10:1660-1669.
