Sodium methyl sulphate

Melting point / freezing point

Administrative data

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

differential scanning calorimetry

Test material

Test material information

Constituent 1

Reference substance name:

Sodium methyl sulphate

EC Number:

208-142-7

EC Name:

Sodium methyl sulphate

Cas Number:

512-42-5

Molecular formula:

CH4O4S.Na

IUPAC Name:

sodium methyl sulphate

Details on test material:

TS-Freetext:
Sodium methyl sulphate
CAS: 512-42-5

Specific details on test material used for the study:

Purity of the test item: 99.9 %
Batch: KIRSCHAZ2-00182

Results and discussion

Melting / freezing point

Key result

Melting / freezing pt.:

>= 206 - <= 210 °C

Atm. press.:

1 013 hPa

Decomposition:

no

Any other information on results incl. tables

Results:

The test item had a melting range starting at 206 °C and ranging up to 210 °C with two pronounced peaks at 207 °C and 209 °C.

Observed thermic procecess:

In the first tests, an endothermal range was found between about RT and about 110 °C

with a distinct maximum at 90 °C. This is due to evaporation of water and is confirmed by the weight loss of 7.6 % after Test 1 and the

weight loss in the TG/DSC-Test of 5.2 % at 96 °C. An additional measurement in a sealed pan to avoid loss of volatiles led to a

sharp endothermal peak at 88 °C, which can be explained by the melting of a hydrate and is an explanation of the maximum in Test 1.

Between about 160 °C and 180 °C, another small endothermal region was found with a rather noisy signal. The additional weight loss

of about 0.2 % (Test 3) speaks for the evaporation of rather strongly bound water.

Therefore, to measure the melting of the dry test item, it was heated first up to 190 °C to evaporate all water, cooled down and then measured.

In these measurements (determination A and B) only a narrow endothermal range between 206 °C and 210 °C was detected with distinct

peaks at 207 °C and 209 °C. That this was the melting of the dry test item is supported by the observation, that e.g. after determination

A (maximum temperature 230 °C) or Test 5 (maximum temperature 215 °C) the test item partly leaked from the crucible.

In order to survey the thermic behavior of the test item a preliminary TG/DSC-Test (non-GLP) was run up to 600 °C.

A decreasing TG-signal starting directly after the melting with a weight loss of about 50 % at 530 °C showed the decomposition of the test item.