Reaction mass of Limestone and dicalcium silicate

Water solubility

Administrative data

Endpoint:

water solubility

Type of information:

migrated information: read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

2010-03-05 to 2010-05-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: The composition and physical-chemical properties of Reaction mass of Limestone and dicalcium silicate are similar to those ones of Lime (chemical), hydraulic.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

yes (High purity water was used instead of glass-double distilled water; No glass was used in critical sample preparation and handling steps)

Principles of method if other than guideline:

Due to the necessity to analyse for silicon, approximately 18 MΩ high purity water was used as an alternative to glass-double distilled water during the preliminary test and the definitive test whilst monitoring
minor components/impurities. It was not appropriate to use water prepared in a glass apparatus due to potential interferences on analysis and in addition, the use of glass was also excluded from critical
sample preparation and handling steps. This deviation was not considered to impact on the validity of the determinations, but was an essential step to generate reliable dissolved silicon data. Glass-doubledistilled
water was used for the definitive test calcium determination.

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Test material

Test material information

Constituent 1

Reference substance name:

Lime (chemical), hydraulic

EC Number:

285-561-1

EC Name:

Lime (chemical), hydraulic

Cas Number:

85117-09-5

IUPAC Name:

85117-09-5

Details on test material:

- Name of test material (as cited in study report): Lime (chemical) hydraulic
- Chemical name: Natural hydraulic lime
- Common name: Chaux Socli NHL 3,5
- Physical state: Grey powder
- Batch No.: XS 060110M1955
- Expiration date of the batch: 2010-07-30
- Storage condition of test material: Room temperature, in the dark

Results and discussion

Water solubility

Water solubility 1

Water solubility:

1 010 mg/L

Temp.:

20 °C

pH:

12.3

Remarks on result:

other: This is the water solubility of calcium as determined in the study. Variation of temperature was ± 0.5 °C.

Water solubility 2

Water solubility:

0.115 mg/L

Temp.:

20 °C

pH:

12.3

Remarks on result:

other: This is the water solubility of iron as determined in the study. Variation of temperature was ± 0.5 °C.

Water solubility 3

Water solubility:

0.305 mg/L

Temp.:

20 °C

pH:

12.3

Remarks on result:

other: This is the water solubility of silicon as determined in the study. Variation of temperature was ± 0.5 °C.

Water solubility 4

Water solubility:

0.158 mg/L

Temp.:

20 °C

pH:

12.3

Remarks on result:

other: This is the water solubility of aluminium as determined in the study. Variation of temperature was ± 0.5 °C.

Details on results:

The preliminary test results indicated that, with exception of one sample (nominal lading rate of 1.0 g/L), no loading rate dependent solubility characterisitcs were observed. For the one sample, elevated
alumnium and silicon concentrations were detected, but it was immediatley obvious that the sample solution was not saturated with respect to the dominant element, calcium. Therefore, this loading rate was
not suitable for the definitive test determination, which should be prepared typically at five times the concentration required to achieve saturation. The reduced calcium concentration of this sample, due to
insufficient test material being present to achieve saturation, possibly allowed the additional dissolution of the aluminium and silicon containing components.
For the definite test (minor components and impurites) an increasing trend in solubilised alumnium concentration with initial saturation time was observed. However, as solubility remained low (<0.2 mg/l)
even after an initial saturation period of 72 hours at 30 °C, no additional testing was considered necessary.

Applicant's summary and conclusion

Conclusions:

Interpretation of results (migrated information): slightly soluble (0.1-100 mg/L)
The water solubility has been determined for four components of lime (chemical) hydraulic. The four components and the water solubility of these are as follows:
1) 1010 mg calcium/L at 20.0 ± 0.5 °C
2) 0.158 mg aluminium/l at 20.0 ± 0.5 °C
3) 0.305 mg silicon/l at 20.0 ± 0.5 °C
4) 0.115 mg iron /l at 20.0 ± 0.5 °C.
An exact water solubility of lime (chemical) hydraulic can not be determined since the molecular formula of the test item is unknown. However, since calcium is the main component of the test material it can
be assumed that the test item is soluble in water.