Neodymium trinitrate

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 24 February 2012 to 27 March 2012

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Key result

Melting / freezing pt.:

> 600 °C

Atm. press.:

ca. 1 atm

Decomposition:

no

Sublimation:

no

Assay No. 1:

Neither endothermic peak nor exothermic peak was recorded.

Assay No. 2:

An endothermic peak was observed at 69.8°C. This endothermic event reflected the fact that the rare earth salt solubilised in its hydration water. Indeed, the hydrated rare earth salts, such as the hydrated form of neodymium trinitrate, loose their water of hydration when heated. As these water molecules are loosely bound and as the amount of water in the substance is significant, the attached water is released and as a result the rare earth salt solubilizes in water. As a result, it is concluded that neodymium nitrate did not melt over the temperature range tested.

No other reaction was recorded up to 600°C.

Assays No. 3 and 4:

The assays No. 3 and 4 were not presented because they were performed in aluminium crucibles and the results were not exploitable. Then the other assays were performed in steel incoloy crucibles with crimped lid. As a result, the test item appearance could not be observed after the DSC procedure.

Assay No. 5:

An endothermic peak was observed at 69.9°C. As for the second preliminary assay, this revealed the solubilisation of the rare earth salt in its hydration water.

Conclusions:

The DSC curve revealed an endothermic peak at 69.9 ± 0.5°C. This endothermic event reflected the fact that the rare earth salt solubilized in its hydration water. As a result, neodymium trinitrate did not melt over the temperature range tested.
No boiling point was recorded up to 600°C, under the experimental conditions tested.

Description of key information

The DSC curve revealed an endothermic peak at 69.9 ± 0.5°C. This endothermic event reflected the fact that the rare earth salt solubilized in its hydration water. As a result, neodymium trinitrate did not melt over the temperature range tested. No boiling point was recorded up to 600°C, under the experimental conditions tested.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

1 374 °C

Additional information

Melting point data obtained from literature.