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1

The effect of chloride ions on alkylbenzenesulfonate degradation in the Fenton reagent

100%
Gaca J., Kowalska M., Mroz M.
Polish Journal of Environmental Studies
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2005
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tom 14
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nr 1
Degradation of sodium alkylbenzenesulfonate (ABS) in the Fenton reagent in the presence of Cl- ions has been studied. An anionic surfactant sodium alkylbenzenesulfonate (C11-C14) has been selected as a model compound. The effect of individual components of the reactive system (H2 O2 , H2 O2 /Cl- , Fe2+/H2 O2 , Fe2+/H2 O2 /Cl- ) on the degree of ABS degradation has been determined. The degree of ABS degradation has been found to be affected by the presence of Cl- ions and the mutual molar ratios of individual components of the system studied. Moreover, it influences on the composition of the post-reaction mixture. The use of the Fenton reagent in the presence of Cl- ions resulted in the formation of chloroorganic compounds in the solution studied. 2,4,6-trichlorophenol was identified in reaction products and its presence was confirmed using the HPLC - MS method and by HPLC with an internal standard. No chloroproducts were identified during degradation of ABS by the system H2 O2 /Cl- . When only H2 O2 was applied, the concentration of the surfactant was unchanged.
2

Toxicity of industrial wastewater treated by Fenton's reagent

100%
Barbusinski K.
Polish Journal of Environmental Studies
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2005
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tom 14
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nr 1
Toxicity of four types of industrial wastewater, treated by Fenton’s reagent, was analyzed. Toxicity was measured using bioluminescent bacteria Vibrio fischeri NRRL B-11177. Application of Fenton’s reagent was a efficient method for treatment of this wastewater. Nevertheless, high efficiency of organic components degradation was not always followed by reduction of toxicity to a very low level. In all cases, in order to achieve total reduction of toxicity, it was necessary to increase both the H2 O2 dose and reaction time. It was concluded that optimization of Fenton’s reaction should be performed assuming toxicity changes in the examined wastewater. Reduction in toxicity should be a critical measure of the success of this method. Such an approach should be general practice in relation to all hazardous industrial wastewater.
3

Use of Fenton's reagent for removal of pesticides from industrial wastewater

100%
Barbusinski K., Filipek K.
Polish Journal of Environmental Studies
|
2001
|
tom 10
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nr 4
The process of pesticide (gamma -HCH and inactive isomers alpha- and beta -HCH, DDT, DMDT, fenitrothion and chlorfenvinphos) removal from industrial wastewater using Fenton's reaction has been analysed. Most of the pesticides were completely degraded at H2O2 Concentration of 2.5 g/dm(3); however, only at 5 g/dm(3) were all the examined pesticides completely removed and the results repeatable. The most effective process was for fenitrothion (from 98.5 to 100%) and chlorfenvinphos (from 97.1 to 100%), whereas organochlorine pesticides were removed with efficiency of more than 90%. The optimum ratio of [Fe2+] to [H2O2] was from 1:3 to 1:2 while the optimum pH was from 3.0 to 3.5. Tests based upon a bioluminescent bacteria Vibrio fischeri NRRL B-11177, at optimized Fenton's reaction parameters, show the reduction of toxicity to non-toxic levels.
4

Simultaneous application of Fenton's reaction and activated sludge method in sequencing batch reactor [SBR]

100%
Janczukowicz W., Krzemieniewski M., Zielinski M., Pesta J.
Polish Journal of Natural Sciences
|
2002
|
tom 12
5

Discoloration of azo dye Acid Red 18 by Fenton reagent in the presence of iron powder

100%
Barbusinski K., Majewski J.
Polish Journal of Environmental Studies
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2003
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tom 12
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nr 2
The examined H2O2/Fe0 process was found to be very efficient for discoloration of simulated wastewater containing 100 mg/dm3 commercial azo dye Acid Red 18. The optimal doses of H2O2 and Fe0 were 60 and 50 mg/dm3, respectively at pH 3 and 15 minutes reaction time. Under the described conditions total visual discoloration was achieved. A very important factor was reaction time. Generally, the smaller dose of iron powder, the greater reaction time needed for visual discoloration. A strict linear correlation was observed between Fe0 amount in the range of 10–600 mg/dm3 and final pH. This suggests that the H2O2/Fe0 process has undoubted advantages in comparison with the classical Fenton reaction, because using excessive amounts of the iron powder could reach higher final pH in the H2O2/Fe0 process. Thus, smaller doses of base will be required for final neutralization of wastewater. It was also found that the dissolution time of iron powder at acidic conditions (before H2O2 was added) is an important parameter that influences the rate of discoloration. As the time of iron powder dissolution increases, the time needed for visual discoloration decreases.
6
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Efficiency of removal of heavy metals from municipal landfill leachate

86%
Koc-Jurczyk J., Jurczyk L.
Journal of Elementology
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2007
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tom 12
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nr 4
327-334
The aim of this study was to determine the rate of removal of heavy metals depending on a treatment method applied to leachate from a municipal waste landfill. After the biological treatment, concentrations of Cu, Zn and Ni were observed to have increased. Application of the reagent Fenton caused further growth in Cu, Zn, and also Pb concentrations. The highest concentrations of Cu, Zn and Ni were observed when the Fe2+: H2O2 ratio in Fenton was 1:3. The lowest concentrations of these heavy metals were observed at a 1:5 ratio of Fe2+ : H2O2. The concentration lead, for example, was over 30-fold higher than in raw leachate. There was not correlation between the COD values in raw leachate or in biologically or chemically processed leachate and the concentrations of the analysed metals.
7

Constant magnetic field influence on stabilization of excess sludge with Fenton's reagent

86%
Debowski M., Krzemieniewski M., Zielinski M.
Polish Journal of Environmental Studies
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2007
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tom 16
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nr 1
The aim of our study was to determine the impact of constant magnetic field (CMF) on the effectiveness of stabilization of the excess sludge by advanced oxidation process with Fenton’s reagent. In presented study raw excess sludge from a dairy wastewater treatment plant was used. The investigations were conducted in three different technological systems in laboratory-scale stands. In the first stage the influence of chemical reagents (Fe²⁺/H₂O₂, Fe³⁺/H₂O₂) on the parameters of sewage sludge was observed. In the secondstage the importance of CMF on the final technological result in the system with static crossing on magnetic field (scCMF) and in the system with cyclical crossing on magnetic field (ccCMF) was revealed. In the third stage of the experiment the effectiveness of the system with both chemical reagents and physical elements was tested. Application of the constant magnetic field let us obtain COD reduction in supernatant and volatile solids in dry mass of sewage sludge. The importance of the physical factor was shown as low doses of chemical reagents. Similar results were achieved independently of the fact if it was tested as the improving element of advanced oxidation with scCMF or with ccCMF.
8

The influence of Fenton reaction on the excess sludge sanitation

72%
Debowski M., Krzemieniewski M.
Archiwum Ochrony Środowiska
|
2005
|
tom 31
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nr 4
9

Effect of sludge conditioning by chemical methods with magnetic field application

72%
Krzemieniewski M., Debowski M., Janczukowicz W., Pesta J.
Polish Journal of Environmental Studies
|
2003
|
tom 12
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nr 5
The feasibility of magnetic field was examined as a factor affecting sludge conditioning intensification. In the experiment sludge after preliminary anaerobic digestion was used, coming from a domestic wastewa­ter treatment plant. Digested sludge was taken directly from a fermentation tank. The experiment was run in three phases. They were performed on a laboratory scale, at various experimental stands. Different dosages of iron chloride, hydrogen peroxide and Fenton's reagent were applied to determine their influence on the sludge properties as well as the effect of constant magnetic field on the conditioning parameters was deter­mined. Straight dependence was found between dosage of the reagents and the way of sludge introduction in the magnetic activity zone, as well as physical and chemical parameters of the prepared sludge.
10

The modified Fenton process for decolorization of dye wastewater

72%
Barbusinski K.
Polish Journal of Environmental Studies
|
2005
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tom 14
|
nr 3
A novel modified Fenton process using heterogeneous catalyst (swarf) was developed to catalyze the oxidation reaction of azo dye Acid Red 18. It was found that swarf could be used to replace iron salts as a catalyst for the Fenton reaction. The examined continuous Fenton process proved to be very efficient for decolorization of simulated wastewater containing 100 mg/dm³ Acid Red 18. Performance of the Fenton reactor and regeneration method of the catalyst was discussed. The simplified mechanism of hydroxyl radical production in the presence of swarf as a catalyst also was proposed.
11

Aerobic sludge digestion in the presence of chemical oxidizing agents. Part II. Fenton's reagent

72%
Barbusinski K., Filipek K.
Polish Journal of Environmental Studies
|
2000
|
tom 09
|
nr 3
Aerobic sludge digestion in the presence of Fenton's reagent and hydrogen peroxide was examined. Fenton's reagent considerably improved the aerobic digestion process in comparison with hydrogen peroxide as well as classical aerobic digestion. Application of Fenton's reagent also led to improvement of settling and dewatering properties of sludge and much better clarity of supernatant. Its drawback, however, is the formation of chemical precipitate and an apparent decrease in pH which might inhibit biochemical processes important for aerobic digestion efficiency.
12

Aerobic sludge digestion in the presence of hydrogen peroxide and Fenton's reagent

72%
Barbusinski K., Filipek K.
Polish Journal of Environmental Studies
|
2003
|
tom 12
|
nr 1
The results of comparative experiments on aerobic digestion of excessive activated sludge using hydrogen,peroxide and Fenton’s reagent are described. Fenton’s reagent was found to have a higher oxidation potential and, as a consequence, higher efficiency in a digestion process in comparison to hydrogen peroxide. Moreover, Fenton’s reagent was shown to improve sedimentation properties of sludge and to decrease soluble COD more efficiently than H2O2. The main advantage of the Fenton’s reagent application was the fact that oxidation processes took place even though Fenton’s reagent was no longer added. On the other hand, the apparent disadvantage of its application is the formation of additional chemical sediments and possible decomposition of sludge flocs as a result of overdosage of reagents and, consequently, an increase in turbidity of supernatant liquid and some difficulties with sludge dewatering.
13

Phenols degradation by Fenton reaction in the presence of chlorides and sulfates

58%
Siedlecka E. M., Stepnowski P.
Polish Journal of Environmental Studies
|
2005
|
tom 14
|
nr 6
Since they often inhibit abundant bacteriological populations in municipal wastewater treatment plants, alternative treatment methods should be investigated – including advanced oxidation processes. This paper studies the degradation of three representatives of phenolic compounds using the Fenton system in the presence of chlorides and sulfates: phenol, 2-chlorophenol and 2-nitrophenol. The presence of anions influenced degradation rates of all studied compounds, which is attributed to the reduction in hydroxyl radical generation due to the formation of iron-complexes as well as the formation of much less reactive inorganic radicals. Differences between degradation rates of studied compounds and their degradation products in comparison to the rates observed for pure components show higher resistance of formed intermediates in comparison to phenol or 2-nitrophenol. Additionally, it was found that present anions influence further biodegradation of phenolic compounds but not similarly for all the compounds.
14

Produkcja płyt MDF bez żywic klejowych

51%
Nicewicz D.
Biuletyn Informacyjny Ośrodka Badawczo-Rozwojowego Przemysłu Płyt Drewnopochodnych w Czarnej Wodzie
|
2015
|
tom 56
|
nr 3-4
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