Tall oil, sodium salt

Auto flammability

Link to relevant study record(s)

Reference

Endpoint:

auto-ignition temperature (liquids)

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2009-11-12 to 2010-03-26

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.15 (Auto-Ignition Temperature (Liquids and Gases))

Version / remarks:

30 May 2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Key result

Auto-ignition temperature:

276 °C

Atm. press.:

ca. 99.17 - ca. 100.85 kPa

The results are shown on the following table:

Test Temperature (ºC)	Test Volume (µl)	Ignition Delay (s)	Observations
50 (Clean Flask)	70	>300	No ignition was observed.
100 (Clean Flask)	70	>300	No ignition was observed.
150 (Clean Flask)	70	>300	No ignition was observed.
200	70	>300	No ignition was observed.
250	70	>300	No ignition was observed.
300	70	>300	No ignition was observed.
350	70	<1	An orange flame was observed. Grey fumes were emitted.
330	70	4	An orange flame was observed. Grey fumes were emitted.
320	70	7	An orange flame was observed. Grey fumes were emitted.
310	70	9	An orange flame was observed. Grey fumes were emitted.

 

306	70	12	An orange flame was observed. Grey fumes were emitted.
302	70	>300	No ignition was observed. Grey fumes were emitted.
304	70	21	An orange flame was observed. Grey fumes were emitted.
302 (Clean Flask)	70	>300	No ignition was observed. Grey fumes were emitted.
302 (Clean Flask)	200	15	An orange flame was observed. Grey fumes were emitted.
300 (Clean Flask)	200	26	An orange flame was observed. Grey fumes were emitted.
296 (Clean Flask)	200	38	An orange flame was observed. Grey fumes were emitted.
292 (Clean Flask)	200	>300	No ignition was observed. Grey fumes were emitted.
294 (Clean Flask)	200	>300	No ignition was observed. Grey fumes were emitted.
294 (Clean Flask)	400	>300	No ignition was observed. Grey fumes were emitted.
294 (Clean Flask)	600	>300	No ignition was observed. Grey fumes were emitted.
294 (Clean Flask)	800	70	An orange flame was observed. Grey fumes were emitted.
292 (Clean Flask)	800	58	An orange flame was observed. Grey fumes were emitted.
290 (Clean Flask)	800	>300	No ignition was observed. Grey fumes were emitted.
290 (Clean Flask)	1000	143	An orange flame was observed. Grey fumes were emitted.
288 (Clean Flask)	1000	>300	No ignition was observed. Grey fumes were emitted.
288 (Clean Flask)	1200	160	An orange flame was observed. Grey fumes were emitted.
286 (Clean Flask)	1200	124	An orange flame was observed. Grey fumes were emitted.
284 (Clean Flask)	1200	>300	No ignition was observed. Grey fumes were emitted.
284 (Clean Flask)	1400	>300	No ignition was observed. Grey fumes were emitted.
284 (Clean Flask)	1600	>300	No ignition was observed. Grey fumes were emitted.

 

Test Temperature (ºC)	Test Volume (µl)	Ignition Delay (s)	Observations
284 (Clean Flask)	1800	>300	No ignition was observed. Grey fumes were emitted.
284 (Clean Flask)	2000	195	An orange flame was observed. Grey fumes were emitted.
282 (Clean Flask)	2000	>300	No ignition was observed. Grey fumes were emitted.
282 (Clean Flask)	2200	207	An orange flame was observed. Grey fumes were emitted.
280 (Clean Flask)	2200	144	An orange flame was observed. Grey fumes were emitted.
278 (Clean Flask)	2200	>300	No ignition was observed. Grey fumes were emitted.
278 (Clean Flask)	2400	>300	No ignition was observed. Grey fumes were emitted.
278 (Clean Flask)	2600	>300	No ignition was observed. Grey fumes were emitted.
278 (Clean Flask)	2800	290	An orange flame was observed. Grey fumes were emitted.
276 (Clean Flask)	2800	136	An orange flame was observed. Grey fumes were emitted.
274 (Clean Flask)	2800	>300	No ignition was observed. Grey fumes were emitted.
274 (Clean Flask)	3000	>300	No ignition was observed. Grey fumes were emitted.
274 (Clean Flask)	3200	>300	No ignition was observed. Grey fumes were emitted.
274 (Clean Flask)	3400	>300	No ignition was observed. Grey fumes were emitted.
274 (Clean Flask)	3600	>300	No ignition was observed. Grey fumes were emitted.

Room temperature:  19 to 20°C

Atmospheric pressure: 99.17 to 100.85 kPa

Conclusions:

An auto-ignition temperature of 276 ± 5 at 99.17 - 100.85 kPa was determined for the substance in a reliable study conducted according to EU Method A.15, and in compliance with GLP.

Description of key information

Auto-ignition temperature: >276°C at 99.17 - 100.85 kPa (EU Method A.15)

Key value for chemical safety assessment

Autoflammability / Self-ignition temperature at 101 325 Pa:

276 °C

Additional information

There are no measured auto-ignition temperatures for the registered substance, TOS. Therefore, auto-ignition temperature data has been read-across from the analogue substance, Crude Tall Oil (CTO).

Crude Tall Oil (CTO) is formed by acidification of Tall Oil Soap (TOS), therefore, CTO and TOS are similar UVCB substances. They differ only in the water content and that CTO does not contain sodium salts of the fatty/rosin acids. The main constituent blocks for TOS are sodium salts of saturated and unsaturated C14-C20 fatty acids (5-45% w/w), rosin acid sodium salts (10-40% w/w), water (25-45% w/w), sterols (1-10% w/w), and non-volatile lignin/cellulose fibre/oligomeric acids (3-20% w/w). In addition, the following minor constituent blocks are present: terpenes, sesquiterpenes, abietenes and labdanes, C30 branched polyalkenes, 3,5-dimethoxystilbene, rosin alcohol and aldehyde isomers and saturated/unsaturated alcohols and terpene alcohols (each <3%).

The same constituents are present in CTO, with only the following differences:

- The fatty acids and rosin acids in Tall Oil Soap (TOS) are present as their sodium salts whereas for Crude Tall Oil (CTO) they are present as acids. In aqueous media, the sodium salts are dissociated into sodium and the parent acid. The sodium, being a ubiquitous and essential element in nature, is not expected to contribute to the toxicity and/or flammability properties of the substance.

- TOS contains 25-45% water compared to trace amounts in CTO; other constituent groups are therefore present at lower levels but in similar proportions. Since both substances are UVCBs, impurities are not relevant as part of the chemical safety assessment.

A reliable auto-ignition temperature value of 276°C at 99.17 - 100.85 kPa has been determined for CTO using an appropriate test method (EU Method A.15) and in compliance with GLP. TOS has a higher amount of water and lower amount of terpenes (volatiles constituents) compared with CTO and as such, it is expected that the auto-ignition temperature of TOS will be greater than that of CTO. Therefore, the auto-ignition temperature of TOS is reported as greater than the value determined for CTO i.e. >276°C for the purpose of the chemical safety assessment. This conclusion is supported by the observation in the differential scanning calorimetry studies conducted for samples of the registered substance. In these studies, limited loss of volatile fractions from about 100°C (373 K) was observed, with formation of significant residue with boiling point >400°C (>673 K) reported. Therefore, it can be concluded that self-heating of the substance can be excluded for the registered substance up to 400°C.

 

There is a strong overlap between CTO and TOS in terms of the chemical constituents present and hence, to an extent and where justified, available data for CTO is considered relevant to be read-across to TOS.