Stability
Phototransformation in air.001
Administrative data
- Purpose flag:
- key study
- Study result type:
- experimental result
- Reliability:
- 2 (reliable with restrictions)
Data source
Reference
- Reference Type:
- publication
- Title:
- Chemical kinetics and photochemical data for use in atmospheric studies.
- Author:
- Sander SP, Friedl RR, Golden DM, Kurylo MJ, Huie RE, Orkin VL, Moortgat GK, Ravishankara AR, Kolb CE, Molina MJ and Finlayson-Pitts BJ
- Year:
- 2003
- Bibliographic source:
- Evaluation no. 14. NASA Jet Propulsion Laboratory, JPL Publication 02-25. 1st February 2003.
Materials and methods
- Principles of method if other than guideline:
- No details of the experimental method are provided.
- GLP compliance:
- no data
Test materials
- Identity of test material same as for substance defined in section 1 (if not read-across):
- yes
Test material identityopen allclose all
Results and discussion
Degradation rate constant
- Reaction with:
- OH radicals
- Rate constant:
- ca. 6.8 cm³ molecule-1 s-1
- Any other information on results incl. tables:
- Table A7_3_1-1: Equilibrium constants for identified reactions(page 3-2; p 64 of 380 viewed as PDF)ReactionA/cm3molecule-1B/°KKeq (298K)f (298K)gNotesCl + O2 → ClOO5.7E-2525002.5E-21275010ClO + O2 → ClO·O22.9E-2637007.2E-2112ClO + ClO → Cl2O21.27E-2787447.0E-151.350013ClO + OClO → Cl2O31.1E-2454559.8E-17330014OClO + NO3 → OClONO21E-2893003.6E-155100015Where K(T)/cm3molecule-1 = A exp (B/T) [200
300K] Table A7_3_1-2: Rate constants for association reactions (termolecular reactions) (from p 2-5; p45 of 380)ReactionLow-pressure limitHigh-pressure limitNotesk0300nk∞300mMCl + O2 → ClOO2.7 ± 1.0 (-33)1.5 ± 0.5--F1MClO + NO2 → ClONO21.8 ± 0.3 (-31)3.4 ± 0.21.5 ± 0.4 (-11)1.9 ± 0.5F8MOClO + NO3 → O2ClONO2----F9MCl O+ ClO → Cl2O21.6 (-32)4.52.0 (-12)2.4F10 *MClO + OClO → Cl2O36.2 ± 1.0 (-32)4.7 ± 0.62.4 ±1.2 (-11)0 ± 1.0F11MOClO + O → ClO31.9 ± 0.5 (-31)1.1 ± 1.03.1 ± 0.8 (-11)0 ± 1.0F12Table A7_3_1-3: Rate constants for other reactions (second-order) (from p 1-16; p 139 of 380)ReactionA factor (cm3molecule-1s-1)E/Rk (298K) (cm3molecule-1s-1)f (298K)gNotesO + ClO → Cl + O23.0E-11-703.8E-111.1570F1O + OClO → Cl + O22.4E-129601.0E-132.0300F2O3 + OClO → products2.1E-1247003.0E-192.51000F7OH + ClO → Cl + HO2→ HCl + O27.4E-126.0E-13-270-2301.8E-111.3E-121.43.0100150F10OH + OClO → HOCl + O24.5E-13-8006.8E-122.0200F11HO2 + ClO → HOCl + O22.7E-12-2205.6E-121.3200F46NO + OClO → NO2 + ClO2.5E-126003.4E-132.0300F48Cl + OClO → ClO + ClO3.4E-11-1605.8E-111.25200F79Cl + ClOO → Cl2 + O22.3E-1002.3E-103.0250F80→ ClO + ClO1.2E-1101.2E-113.0250F80ClO + O3 → ClOO + O2→ OClO + O2-1E-12->40001.4E-171.0E-18----F109ClO + H2 → products-1E-12>48001.0E-19--F110ClO + NO → NO2 + Cl6.4E-12-2901.7E-111.15100F111ClO + NO3 → ClOO + NO24.7E-1304.7E-131.5400F112ClO + NO2 → products~1.0E-12>43006.0E-19--F113ClO + CO → products~1.0E-12>37004.0E-18--F114ClO + CH4 → products~1.0E-12>37004.0E-18--F115ClO + H2CO → products~1.0E-12>21001.0E-15--F116ClO + CH3O2 → products3.3E-121152.2E-121.5115F117ClO + ClO → Cl2 + O2→ ClOO + Cl→ OClO + Cl1.0E-123.0E-113.5E-131590245013704.8E-158.0E-153.5E-151.51.51.5300500300F118f(298K) is the uncertainty at 298K
Applicant's summary and conclusion
Phototransformation in air.002
Administrative data
- Purpose flag:
- supporting study
- Study result type:
- experimental result
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- Test not undertaken to international guidelines or GLP, but well designed and undertaken under carefully controlled conditions.
Data source
Reference
- Reference Type:
- publication
- Title:
- Photodecomposition of chlorine dioxide and sodium chlorite in aqueous solution by irritatin with ultraviolet light.
- Author:
- Cosson H and Ernst WR
- Year:
- 1994
- Bibliographic source:
- Industrial Engin. Chem. Res., 33: 1468-1475
Materials and methods
Test guideline
- Qualifier:
- no guideline followed
- Deviations:
- not applicable
- GLP compliance:
- no
Test materials
- Identity of test material same as for substance defined in section 1 (if not read-across):
- yes
Test material identityopen allclose all
- Identifier:
- CAS number
- Identity:
- 10049-04-4
- Identifier:
- EC number
- Identity:
- 233-162-8
- Identifier:
- IUPAC name
- Identity:
- chlorous acid
- Details on test material:
- 0.1 M pure chlorine dioxide (7 g/L) in a brown bottle stored in refrigerator.
Study design
- Light source:
- other: mercury discharge lamp
- Light spectrum: wavelength in nm:
- >= 253.7 - 300
- Details on test conditions:
- ubstance concentration: 0.020 - 0.024 mol/l
Spectrum of substance: Maximum molar extinction (Imax) at 370 nm
Test medium: Unbuffered deionised water solutions.
Duration: Until 100 minutes Irradiation conditions: 90% transmission measured down to 200 nm. Maximum of 240 W.
Results and discussion
- Test performance - Remarks:
- Concentration of substance: 0.020 - 0.024 mol/l Products: Chlorine dioxide residual concentration vs. time. Quantum Yield (number of chlorine dioxide molecules divided by the number of photons adsorbed by the solution): 1.4 at 300 nm and 0.44 at 253.7 nm, both at 25 deg. C.
- Quantum yield (for direct photolysis):
- 1.4
Applicant's summary and conclusion
Hydrolysis.004
Administrative data
- Purpose flag:
- weight of evidence
- Study result type:
- experimental result
- Reliability:
- 2 (reliable with restrictions)
- Rationale for reliability incl. deficiencies:
- Scientifically justified results, but not following guideline.
Data source
Reference
- Reference Type:
- review article or handbook
- Title:
- Unnamed
- Year:
- 2010
- Report Date:
- 2010
Materials and methods
Test guideline
- Qualifier:
- no guideline available
- Principles of method if other than guideline:
- For the determination of chlorite in water samples Ion Chromatography (IC) is used. Samples were quantified using a calibration curve. The ions are separated in a column and the concentration is measured by conductivity. Positive ions are exchanged to hydrogen ions in a suppressor. The eluent is NaOH with a concentration of 0.01 M. The calibration standards are prepared from a commercial stock solution. For reporting limit 0.01 mg/l chlorite 200 μl sample is injected and for reporting limit 0.005 mg/l 400 μl is used. Every sample is also analyzed with an addition of chlorite standard to confirm the identity of the chlorite peak.
Analytical procedure
Ion chromatograph: Dionex ICS-1000
Autosampler: Dionex AS40
Column: IonPac Dionex AS23, 4X250 mm
Suppressor: Dionex ASRS ULTRA II 4 mm
Eluent: 0.01M NaOH
Injection volume: 200 μl and 400 μl
Flow rate: 1 ml/min
Integration software: Chromeleon vers. 6.5
Performance
For preparing the standards a commercial stock solution was used. New standard was made for every new calibration curve. The calibration series was diluted in MQ-water and in the concentration range of 0.01-5 mg/l and 0.005-5 mg/l chlorite. The samples were filtrated over a 0.45μm filter before analyzing. A standard was analyzed between every sample to check the stability over the calibration curve. - GLP compliance:
- no data
Test materials
- Identity of test material same as for substance defined in section 1 (if not read-across):
- no
Test material identityopen allclose all
- Identifier:
- CAS number
- Identity:
- 7758-19-2
- Identifier:
- CAS number
- Identity:
- 10049-04-4
- Details on test material:
- No data
- Radiolabelling:
- no
- Details on properties of test surrogate or analogue material:
- No data
Study design
- Analytical monitoring:
- no data
- Details on sampling:
- No data
- Buffers:
- No data
- Details on test conditions:
- No data
- Number of replicates:
- No data
- Positive controls:
- no data
- Negative controls:
- no data
- Statistical methods:
- No data
Results and discussion
- Preliminary study:
- No data
- Test performance:
- No data
- Transformation products:
- no data
- Details on hydrolysis and appearance of transformation product(s):
- No data
Total recovery of test substance (in %)open allclose all
- % Recovery:
- ca. 100
- Duration:
- ca. 4 - < 7 h
- % Recovery:
- >= 94
- Duration:
- ca. 7 h
Dissipation half-life of parent compound
- Half-life:
- ca. 8 h
- Remarks (e.g. regression equation, r², DT90):
- Study 1
- Any other information on results incl. tables:
- Table 1: Aerobic abiotic and biotic degradation of chlorite in freshwater.Test substanceSystemInitial concentrationsMethodDegradationReferenceSodium chloriteNatural river water (Mölndalsån) TOC 8 mg/L0.025, 0.05, 0.075, 0.1 mg/LFurther to addition of the appropriate concentrations of chlorite, samples were taken at 0, 1, 4, 8 and 16 h and immediately analysed using ionic chromatographyA half-life of approximately 8 h was observed at the lowest concentration. Longer half-lives were noted for higher concentrationsEKA Chemicals internal report (in prep)Sodium chloriteNatural river water TOC 17 mg/L0.025, 0.05, 0.075, 0.1 mg/LFurther to addition of the appropriate concentrations of chlorite, samples were taken at 7, 16 and 48 h and immediately analysed using ionic chromatographyThe 2 lowest concentrations were below LOQ (0/005 mg/L) within 4 h, 0.075 mg/L was <LOQ within 7 h and 0.1 mg/L was at 0.006 mg/L at this timeEKA Chemicals internal report (in prep)Sodium chloriteNatural river water (Dalån) TOC 19 mg/L0.025, 0.05, 0.075, 0.1 mg/LFurther to addition of the appropriate concentrations of chlorite, samples were taken at 2, 4 and 7 h and immediately analysed using ionic chromatographyAll concentrations were below LOQ (0/005 mg/L) in a time period of <7h (the shortest measurement period)EKA Chemicals internal report (in prep)
Applicant's summary and conclusion
********************************************
Hydrolysis.003
Administrative data
- Purpose flag:
- key study
- Study result type:
- experimental result
- Reliability:
- 2 (reliable with restrictions)
Data source
Reference
- Reference Type:
- publication
- Title:
- Stability of chlorine dioxide in aqueous solution
- Author:
- Medir M and Giralt F
- Year:
- 1982
- Bibliographic source:
- Water Res., 16, 1379-1382
Materials and methods
- Principles of method if other than guideline:
- Chlorine dioxide was prepared from 20 % sodium chlorite (commercial grade) solution by dropwise addition of 1N sulfuric acid. The generated chlorine dioxide was swept from the solution using nitrogen as carrier, passed through sodium chlorite solution to remove any chlorine formed and dissolved in double distilled water or in an aqueous solution of sodium chloride placed in the reaction vessel.
Reactions were carried out at 25°C in a jacketed pyrex glass reaction vessel of 500 mL protected from light and in the absence of gaseous phase. The pH was maintained constant at 9 by automatic addition of sodium hydroxide from a burette controlled by a pH-stat.
Experiments were carried out in sodium chloride concentrations of 0, 0.1, 0.4, 0.8 or 2.0 mol/L. Initial concentrations of chlorine dioxide were between 0.002-0.02 mol/L.
The initial concentration of chlorine dioxide was determined by acid-neutral iodometric titration with sodium thiosulfate. Chlorine dioxide consumption was determined by recording the addition of sodium hydroxide. Chlorine dioxide, chlorite and chlorate concentrations were determined by iodometric titration with sodium thiosulfate at different pH values. The chloride concentration was determined by titration with silver nitrate solution using both the Mohr method and the potentiometric method for detection of end point, after flushing the remaining chlorine dioxide out of the solution. - GLP compliance:
- no data
Test materials
- Identity of test material same as for substance defined in section 1 (if not read-across):
- yes
Test material identityopen allclose all
- Identifier:
- CAS number
- Identity:
- 10049-04-4
- Identifier:
- EC number
- Identity:
- 233-162-8
- Details on test material:
- - Analytical purity:
Not reported, however expected to be close to 100 % due to the method of production.
- Other:
Chlorine dioxide was prepared from 20 % sodium chlorite (commercial grade) solution by dropwise addition of 1N sulfuric acid. The generated chlorine dioxide was swept from the solution using nitrogen as carrier, passed through sodium chlorite solution to remove any chlorine formed and dissolved in double distilled water or in an aqueous solution of sodium chloride placed in the reaction vessel. - Radiolabelling:
- no
Study design
- Analytical monitoring:
- yes
- Details on test conditions:
- Reactions were carried out at 25 °C in a jacketed pyrex glass reaction vessel of 500 mL protected from light and in the absence of gaseous phase. The pH was maintained constant at 9 by automatic addition of sodium hydroxide from a burette controlled by a pH-stat.
Experiments were carried out in sodium chloride concentrations of 0, 0.1, 0.4, 0.8 or 2.0 mol/L. Initial concentrations of chlorine dioxide were between 0.002-0.02 mol/L.
Duration of test
- Duration:
- 400 min
- pH:
- 9
- Temp.:
- 25 °C
- Initial conc. measured:
- >= 0.002 - <= 0.02 mol/L
- Number of replicates:
- One test performed for each set of conditions.
- Positive controls:
- no data
- Negative controls:
- no data
Results and discussion
- Preliminary study:
- Not applicable
- Transformation products:
- yes
- Details on hydrolysis and appearance of transformation product(s):
- In the presence of sodium chloride, the degradation products were chlorite and chlorate in a 1:1 ratio.
In the absence of sodium chlorite, the degradation products were chlorate, chlorite, chloride and oxygen in a 5:3:1:0.75 ratio.
- Details on results:
- In aqueous solution at pH 9 there is a slow initial hydrolysis reaction followed by a more rapid one (Figure 1). The shape of the curve is indicative of an autocatalytic reaction. The length of the induction period for the second reaction is dependent of the concentration of the chlorine dioxide (at 0.02M the induction period is < 100 minutes, whereas at 0.003M the induction period is > 400 minutes). The degradation products are chlorate, chlorite, chloride and oxygen in a 5:3:1:0.75 ratio.
In the presence of sodium chloride there is a slow reaction of a few minutes duration (which is not appreciable in Figure 2) followed by a second faster reaction, which does not present an autocatalytic shape. The degradation products are chlorite and chlorate in a 1:1 ratio.
Applicant's summary and conclusion
- Conclusions:
- Aqueous solutions of chlorine dioxide are fairly stable at 25°C and pH 9 for an initial period of time before a fast decomposition takes place. The length of the initial stable period decreases with increasing chlorine dioxide concentration and in the presence of inert electrolytes. The reaction products are chlorate, chlorite, chloride and oxygen. Addition of sodium chloride reduces significantly the induction time, but slows down the second reaction and changes the product distribution to equal amounts of chlorite and chlorate.
- Validity criteria fulfilled:
- not applicable
*********************************
Hydrolysis.002
Administrative data
- Purpose flag:
- weight of evidence
- Study result type:
- experimental result
- Reliability:
- 2 (reliable with restrictions)
Data source
Reference
- Reference Type:
- study report
- Title:
- Unnamed
- Year:
- 2009
- Report Date:
- 2009
Materials and methods
Test guideline
- Qualifier:
- no guideline followed
- Principles of method if other than guideline:
- The chemical model used to understand the disappearance of disinfection residuals (chlorine dioxide, chlorite and chlorate) in ballast water treated with up to 5 mg/L chlorine dioxide is based on analytical data gathered from numerous studies of treated waters from various locations world-wide.
Consider that a defined volume of water previously treated with chlorine dioxide and having a residual concentration of about 1 mg/L chlorine dioxide (e.g., treated ballast) is diluted with an equal volume untreated water. If no additional demand is contained in the dilution water one would expect
to see a 50% reduction in concentration due to the 1:1 dilution … or a concentration of 0.5 mg/L. - GLP compliance:
- no
Test materials
- Identity of test material same as for substance defined in section 1 (if not read-across):
- yes
Test material identityopen allclose all
- Identifier:
- CAS number
- Identity:
- 10049-04-4
- Identifier:
- CAS number
- Identity:
- 7758-19-2
- Identifier:
- CAS number
- Identity:
- 7775-09-9
- Details on test material:
- - Name of test material (as cited in study report): Chlorine dioxide, chlorite, chlorate
- Molecular formula (if other than submission substance): ClO2, ClO2-, and ClO3-
No other information. - Radiolabelling:
- no
- Details on properties of test surrogate or analogue material:
- no data
Study design
- Analytical monitoring:
- yes
- Details on sampling:
- no data
- Buffers:
- no data
- Details on test conditions:
- no data
- Number of replicates:
- no data
- Positive controls:
- no data
- Negative controls:
- no data
- Statistical methods:
- no data
Results and discussion
- Preliminary study:
- no data
- Transformation products:
- yes
Identity of transformation productsopen allclose all
- No.:
- #1
- Identifier:
- common name
- Identity:
- Chlorite ion
- No.:
- #2
- Identifier:
- common name
- Identity:
- Chlorate ion
- Details on hydrolysis and appearance of transformation product(s):
- - Formation and decline of each transformation product during test: ClO2 --> ClO2- + e-
- Pathways for transformation: ClO2 --> ClO2- --> ClO3-
- Other: none
- Other kinetic parameters:
- no data
- Details on results:
- 5 mg/L ClO2 is typically undetectable within 24 hours of application…in most applications it is undetectable within 1-2 hours
ClO2 does not chlorinate, thus chlorinated by-products are not observed
ClO2 reacts to form primarily chlorite (ClO2-) and chlorate (ClO3-)…the initial chlorate level is typically <10% of the applied dose
ClO2, ClO2- and ClO3- have shown demand in both the NIOZ and NJ source waters
ClO2, ClO2- and ClO3- will quickly react (minutes time-scale) with untreated dilution water to lower the residual concentration below measurement detection levels…the worst case from the various studies (NIOZ and shipboard) indicate that 9 dilution volumes are required to lower the concentration of all residual species to undetectable levels within 2 minutes.
Initial rate data indicate that the reactions of chlorine dioxide and chlorite in untreated waters is fast
The loss in chlorate upon dilution is believed to involve the enzyme nitrate-reductase (NR)
The complete reaction of chlorine dioxide and its by-products is believed to result in the formation of chloride ion ClO2 → ClO2- → → Cl-→ ClO3- → → Cl- - Any other information on results incl. tables:
- All the figures are presented in attached files.Figure 1: NJ Ballast Water Chlorine dioxid demand 5.05 mg/L, 24°CFigure 2: Chlorine dioxide demand NIOZ Low salinity waterFigure 3: Chlorite ion demand study NIOZ 0.98 mg/L, ambientFigure 4: Chlorate ion demand study NIOZ 1.8 mg/L, ambientFigure 5: Chlorine dioxide dilution demand NIOZ 1.82 mg/L, ambientFigure 6: Chlorite dilution demand NIOZ 1 mg/L, ambientFigure 7: Chlorite dilution demand NJ water 1.4 mg/L, 20°CFigure 8: Chlorate dilution demand NIOZ 1.57 mg/L, ambientFigure 9: Chlorate dilution demand NJ water 1.5 mg/L, 20°C
Applicant's summary and conclusion
- Conclusions:
- The presented data show that any chlorine dioxide residuals that might be present following the treatment of ballast water will quickly be consumed by dilution and demand.
- Executive summary:
- Chlorine dioxide, chlorite and chlorate show similar demand features when tested in diverse waters… NIOZ (The Netherlands); NJ (East Coast USA). Both waters show an initial fast demand for chlorine dioxide along with a slower continuing loss of chlorite and chlorate ions. Dilution of the treated water with the source water shows demand for chlorine dioxide, chlorite and chlorate beyond what can be accounted for by dilution. This dilution-demand act to further remove any residuals that might be present at the time of ballast release. The initial rate of chlorine dioxide loss appears to be relatively constant however increases are observed for more industrial source waters compared to more pristine source waters. The initial rate of chlorite ion loss appears to be similar to NIOZ and NJ source waters regardless of temperature.The initial rate of chlorate ion loss in NIOZ water appears to be temperature dependent and is thought to involve the enzymatic reaction of nitrate-reductase.
- Validity criteria fulfilled:
- yes
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