Reaction mass of calcium carbonate and calcium dihydroxide and calcium peroxide

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Well documented GLP study according to OECD and other internationally accepted guidelines. No deviations.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

2012

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

yes

Type of method:

flask method

Test material

Test material information

Constituent 1

Reference substance name:

reaction mass of calcium carbonate and calcium dihydroxide and calcium peroxide

EC Number:

908-343-6

Molecular formula:

The substance is a reaction mass of a number of constituents and so the molecular formula of the substance to be registered is not available

IUPAC Name:

reaction mass of calcium carbonate and calcium dihydroxide and calcium peroxide

Details on test material:

- Physical state: light yellow powder
- Composition of test material, percentage of components:
- 77.8% CaO2
- 6.7% CaCO3
- 15.5% Ca(OH)2
- 0.1% H2O
- Lot/batch No.: 20100601
- Expiry date: 16 february 2012
- Stability under storage conditions: stable
- Storage condition of test material: at room temperature in the dark

Results and discussion

Water solubility

Water solubility:

> 0.1 g/L

Temp.:

20 °C

Remarks on result:

other: From preliminary test.

Details on results:

An exact water solubility value cannot be determined by measurement of calcium peroxide but has to be estimated from calcium content, H2O2 content and pH.

Any other information on results incl. tables

Three mixtures of water and the test substance were stirred for 24, 48 and 96h, whereafter calcium content, hydrogen peroxide content and pH were measured. Quantitative analysis of calcium and hydrogen peroxide was performed according to analytical methods that were validated in separate experiments.

100 mg/L test vessel:

Ca conc. after 24 - 48 - 96h: 0,0512 - 0,0550 - 0,0526 g/L

Hydrogen peroxide conc. after 24 - 48 - 96h: 0,09 - 4,42 - < 0,09 - < 0,09 mg/L

pH: 11,3

1000 mg/L test vessel

Ca conc. after 24 - 48 - 96h: 0,136 - 0,164 - 0,194 g/L

Hydrogen peroxide conc. after 24 - 48 - 96h: 4,04 - 0,821 - 1,21 mg/L

pH: 12,1 - 12,2

10000 mg/L test vessel

Ca conc. after 24 - 48 - 96h: 0,451 - 0,697 - 0,750 g/L

Hydrogen peroxide conc. after 24 - 48 - 96h: 2,61 - 0,362 - 0,311 mg/L

pH: 12,4 - 12,7

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): moderately soluble (100-1000 mg/L)
The water solubility can not be determined by measurement of calcium peroxide.
Nevertheless, quantitative measurement of the calcium content of a 100 mg/L solution in the preliminary test showed that the water solubility is > 0,1 g/L

Executive summary:

The water solubility is a property of pure substances and therefore a water solubility study is not really applicable for reaction masses. However, the pure substance calcium peroxide does not exist and therefore a combined water solubility / hydrolysis study was conducted with the reaction mass of calcium carbonate and calcium dihydroxide and calcium peroxide.

The water solubility was assessed via the flask method. Three mixtures of water and the test substance were stirred for 24, 48 and 96h, and were centrifuged to remove any undissolved material. Afterwards calcium content, hydrogen peroxide content and pH were measured. Quantitative analysis of calcium and hydrogen peroxide was performed according to analytical methods that were validated in separate experiments.

An exact water solubility value cannot be determined by measurement of calcium peroxide due to its reactivity when brought into contact with water. Nevertheless, an indicative value for the water solubility can be estimated from calcium content, hydrogen peroxide content and pH. From the experiment it can be deduced that the solubility is > 0,1 g/L, but less than 1 g/L under the conditions of the test.