Naphthenic acids, bismuth salts

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:

July 2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

GLP compliance:

no

Type of method:

method to determine freezing temperature

Specific details on test material used for the study:

As the sample is exclusively produced and placed on the market in mineral oil, which cannot be removed from the product sufficiently, a pure sample was manufactured by using a volatile hydrocarbon solvent that could be removed afterwards. Thus, an almost pure sample was derived that was used for testing.

Melting / freezing pt.:

> -12 - < 2.4 °C

Atm. press.:

1 atm

Decomposition:

no

Conclusions:

The sample bismuth naphthenate analysed showed a freezing temerature in the range of -12 - 2.4 °C.

Executive summary:

A purified sample of bismuth naphthenate has been investigated for its freezing temperature by using an Gehaka PF1500 apparatus with a lower limit of 2.5 °C. At that temperature, the sample was still liquid. Hence, the material was stored in a freezer at -12 °C for 12 hours and was found not flowing anymore but being still transparent and shiny. Hence, the solidification point is in the range of -12 – 2.4 °C. Further investigation is not required.

Description of key information

The purified sample is liquid at room temperature and does solidify in a freezer at -12 °C when being stored there for 12 hours. However, the sample remained transparent and shiny and thus the value between -12 and +2.4 °C is to be seen as solidifying temperature rather than as melting point temperature.

As the product is manufactured and placed on the market solely dissolved in mineral oil (typical concentration 30% w/w) the exact solidification/melting point is not of particular relevance. For hazard and risk assessment purposes a solidification temperature of -12 °C is further used.

Key value for chemical safety assessment

Melting / freezing point at 101 325 Pa:

-12 °C