Sulfuric acid, mono-C9-12-alkyl esters, sodium 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:

March 10 - 11, 2016

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing 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

Decomposition:

yes

Decomp. temp.:

ca. 190 °C

MELTING TEMPERATURE (PHOTOCELL DETECTION):

The sample was found to undergo suspected decomposition without melting around 190°C. No melting was observed to 350°C (as sample transformed into a carbonaceous mass in the capillary tube).

DSC Method:

A sample of C9-C12 alkyl sulfate, sodium salt was charged to an open aluminium DSC crucible and placed in the furnace. The sample was then ramped from 25°C to 500°C at 4 K.min-1.

Test A

The test was conducted in an open aluminium crucible. The sample was observed to undergo an endothermic event from 35.29°C (-4.50 J.g-1). Another endothermic event was then observed to commence from 59.37°C which had a heat of melting of -15.51 J.g-1. A further endothermic event was observed from 188.73°C (-54.35 J.g-1). A 4th endothermic event was observed at 201.23°C with a heat of melting of 31.32 J.g-1. This was followed by an exothermic event at 208.64°C with a heat of decomposition of 14.78 J.g-1. The last endothermic event was observed at 251.53°C (-146.69 J.g-1). Brown / black residue was left in the crucible.

Test B The test was conducted in an open aluminium crucible. The sample was observed to undergo an endothermic event (melting) from 38.01°C (-5.75 J.g-1). Another endothermic event was then observed to commence from 60.21°C which had a heat of melting of -15.64 J.g-1. A further endothermic event was observed from 188.56°C (-59.25 J.g-1). The 4th endothermic event was observed at 201.14°C with a heat of melting of 36.41 J.g-1. This was followed by an exothermic event at 208.72°C with a heat of decomposition of 15.69 J.g-1.The last endothermic event was observed at 252.02°C (-154.44 J.g-1). Brown / black residue was left in the crucible.

Result : Not determined

Description of key information

Decomposition at ca. 190 °C (EU A.1)