Benzenesulfonic acid, 4-mono-C20-24 (even numbered)-alkyl derivs., magnesium salts

Boiling point

Link to relevant study record(s)

Reference

Endpoint:

boiling point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2012-09-20 - 2012-12-19

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study with certificated GLP compliance. No methodology deficiencies are reported.

Qualifier:

according to guideline

Guideline:

OECD Guideline 103 (Boiling point/boiling range)

Qualifier:

according to guideline

Guideline:

EU Method A.2 (Boiling Temperature)

GLP compliance:

yes (incl. QA statement)

Remarks:

The Department of Health of the Government of The United Kingdom

Type of method:

differential scanning calorimetry

Boiling pt.:

327 - 400 °C

Atm. press.:

98.7 kPa

Remarks on result:

other: The test substance partially boils in the mentioned temperature range.

Table 1. Thermographic Data - Determination 1

Thermal Event	Interpretation	Temperature
		°C	K
Endotherm	Onset of partial boiling	326.55	599.70
	Extrapolated onset of partial boiling	368.08	641.23
	Peak of partial boiling	375.65	648.80

Table 2. Thermographic Data - Determination 2

Thermal Event	Interpretation	Temperature
		°C	K
Endotherm	Onset of partial boiling	330.41	603.56
	Extrapolated onset of partial boiling	370.72	643.87
	Peak of partial boiling	376.91	650.06

After being heated up to 400 °C the test substance had changed from a dark brown liquid to a residue that was a very dark brown viscous liquid/paste that had flowed to the periphery of the crucible.

Conclusions:

The study report describes a valid guideline study conducted under certificated GLP compliance. The test substance partially boils from approximately 327 to 400 °C at 98.7 kPa.

Executive summary:

Differential scanning calorimetry (DSC) was used to determine the boiling point of magnesium sulfonate target substance (CAS 231297-75-9) (Fox, 2012). In the calorimeter, two identical crucibles, one filled with the test substance and the other empty (used as reference), were heated at a constant rate. The difference in heat flow between both crucibles was registered. The calibration of the DSC was performed with an indium reference standard and considered as acceptable. Two determinations were performed within a temperature range of 20 °C to 400 °C at a heating rate of 20 °C/min. After being heated up to 400 °C, the test substance was observed as a dark brown viscous liquid/paste flowing to the periphery of the crucible. A significant amount of the test substance consists of oil (~ 48 %), therefore the endotherm observed is possibly due to partial boiling of this oil. The loss of some of the more volatile oil components would then explain why the test substance become more viscous after heating. In general, the boiling point depends on the atmospheric pressure. A correction to normalized pressure can be made, but the correction factor is a specific parameter for each test substance and has to be determined individually. No correction is applied to the observed boiling point, thus the value is stated with regard to the ambient pressure during the experiment. As overall result it is reported, that the test substance partially boils in a temperature range of approximately 327 °C to 400 °C.

Description of key information

OECD 103/EU Method A.2_Boiling range: 327 - 400 °C

Key value for chemical safety assessment

Boiling point at 101 325 Pa:

327 °C

Additional information

The test substance partially boils from approximately 327 - 400 °C (Fox, 2013). This was determined using differential scanning calorimetry (DSC) in accordance to OECD Guideline 103 / EU Method A.2.