Naphthenic acids, nickel 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:

2018-01-04 to 2018-08-22

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Version / remarks:

2008

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: OECD Test Guideline 113 Thermal Stability

Version / remarks:

1981

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

signed 2017-02-28

Type of method:

differential scanning calorimetry

Specific details on test material used for the study:

Storage conditions: Room temperature tightly closed

Atm. press.:

>= 1 002 - <= 1 003 hPa

Decomposition:

yes

Decomp. temp.:

> 200 °C

Melting and Boiling Point (DSC)

The thermograms of the DSC runs PN15109 and PN15118 shows in the temperature range of 250 °C to 410 °C, an endothermic. No further thermal effects were observed up to the test end temperature of 600 °C.

Results of the DSC-measurements

No.	Sample weight [mg]	Onset of Effect [°C]	Range of effect [°C]	Weight loss [mg]	Atmospheric pressure [hPa]
PN15109	11.35	327.33	280 – 41 (endo)	9.47 83 %	979.8
PN15118	11.58	319.63	250 – 400 (endo)	10.08 87 %	984.1

During the cooling phase, no thermal effects were observed, which can be assigned to the freezing of the test item.

During the heating phase the test item showed an endothermic signal in the temperature range of 250 °C to 410 °C which cannot definitely assigned to the boiling of the test item.

In view of the fact that the measured weight loss of each sample was only between 83 % and 87 % of the respective initial sample weight, the observed endothermic effect cannot be definitely assigned to the boiling of naphthenic acid, nickel salts.

Measurements by the Test Tube

Due to the fact that no melting peak in the DSC was observed, the melting of the test item was verified in a test tube. In the temperature range of -30 to approx. -5 °C the test item was solid. The appearance of the test item during warming up was at approx. 2 °C very pasty and at 10 °C viscous paste. The test item shows a softening in the temperature range of approx. -5 °C to 0 °C.

Measurements by the Capillary Method

For verification of the results the test item was additionally tested with the capillary method. The test item started to change the colour at ~200 °C from green to partly black at the top of the capillary. At approx. 230 °C it was completely black, at ~250 °C grey and transparent. The measurement was stopped at 400 °C with a black residue remaining in the capillary. No boiling of the test item could be observed. It is assumed, that the test item decomposes at temperatures >200 °C.

Thermal Stability (DSC)

The test item naphthenic acid, nickel salts showed in the DSC runs PN14366 and PN14367 an endothermic effect in the temperature range of 290 °C - 420 °C. An exothermic effect started at a temperature of 470 °C with a maximum energy of -60 J/g accompanied by a pressure rise.

Results of the DSC-measurements

No.	Sample weight [mg]	Start of effect [°C]	Energy* [J/g]
PN14366	8.85	320 (endotermic) 470 (exothermic)	+220 >-40
PN14367	5.15	290 (endotermic) 490 (exothermic)	+300 >-60

 *Negative energy for exothermic processes, positive energy for endothermic processes

Conclusions:

Melting and Boiling Point
No definitive signs of melting and boiling of the test item naphthenic acid, nickel salts were observed by differential scanning calorimetry (DSC) measurements (open aluminium crucible under air, from -100 °C up to 600 °C, heating rate of 10 K/min). The measurements were performed according to Regulation (EC) No. 440/2008 Method A.1/A.2 and OECD Test Guideline 102/103 (1995) at atmospheric pressure (1002 – 1003 hPa).
In a test tube the test item shows a softening in the temperature range of approx. -5 °C to 0 °C at atmospheric pressure (1003 hPa).
No definitive signs of boiling of the test item naphthenic acid, nickel salts were observed by differential scanning calorimetry (DSC) measurements (open aluminium crucible under air, up to 600 °C, heating rate of 10 K/min) and by the capillary method (up to 400 °C, heating rate of 10 K/min). The measurements were performed according to Regulation (EC) No. 440/2008 Method A.2. and OECD Test Guideline 103 (1995) at atmospheric pressure (1002 – 1003 hPa). It is assumed that the test item decomposes at temperatures >200 °C.

Thermal Stability
In DSC measurements (closed glass crucible under air, from room temperature up to 600 °C, heating rate of 3 K/min) according to OECD guideline 113 (1981) the test item naphthenic acid, nickel salts showed an endothermic effect in the temperature range of 300 °C - 420 °C, an exothermic effect starting at a temperature of 470 °C with a maximum energy of -60 J/g accompanied by a pressure rise.

Description of key information

No definitive signs of melting and boiling of the test item naphthenic acid, nickel salts were observed. It is assumed that the test item decomposes at temperatures >200 °C.

Additional information

Melting and Boiling Point

No definitive signs of melting and boiling of the test item naphthenic acid, nickel salts were observed by differential scanning calorimetry (DSC) measurements (open aluminium crucible under air, from -100 °C up to 600 °C, heating rate of 10 K/min). The measurements were performed according to Regulation (EC) No. 440/2008 Method A.1/A.2 and OECD Test Guideline 102/103 (1995) at atmospheric pressure (1002 – 1003 hPa).

In a test tube the test item shows a softening in the temperature range of approx. -5 °C to 0 °C at atmospheric pressure (1003 hPa).

No definitive signs of boiling of the test item naphthenic acid, nickel salts were observed by differential scanning calorimetry (DSC) measurements (open aluminium crucible under air, up to 600 °C, heating rate of 10 K/min) and by the capillary method (up to 400 °C, heating rate of 10 K/min). The measurements were performed according to Regulation (EC) No. 440/2008 Method A.2. and OECD Test Guideline 103 (1995) at atmospheric pressure (1002 – 1003 hPa). It is assumed that the test item decomposes at temperatures >200 °C.

Thermal Stability

In DSC measurements (closed glass crucible under air, from room temperature up to 600 °C, heating rate of 3 K/min) according to OECD guideline 113 (1981) the test item naphthenic acid, nickel salts showed an endothermic effect in the temperature range of 300 °C - 420 °C, an exothermic effect starting at a temperature of 470 °C with a maximum energy of -60 J/g accompanied by a pressure rise.