Registration Dossier

Administrative data

Endpoint:
appearance / physical state / colour
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2016-10-31 to 2016-12-22
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Results obtained from a melting point/boiling point determination test according to OECD Guideline and GLP
Cross-reference
Reason / purpose:
reference to same study
Reference
Endpoint:
melting point/freezing point
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2016-10-31 to 2016-12-22
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to
Guideline:
OECD Guideline 102 (Melting point / Melting Range)
Version / remarks:
adopted 27 July, 1995
Deviations:
no
Qualifier:
according to
Guideline:
EU Method A.1 (Melting / Freezing Temperature)
Version / remarks:
30 May, 2008
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of method:
differential scanning calorimetry
Key result
Melting / freezing pt.:
115 °C
Atm. press.:
1 013 Pa
Decomposition:
yes
Decomp. temp.:
> 180 °C
Sublimation:
no

A preliminary thermogravimetric measurement was performed over a temperature range from room temperature to approx. 600 °C. Two steps were registered with maxima at 226 °C resp. 427 °C. A total mass loss of 86.3 % at the final temperature could be observed (mass change in the range until 360 °C: - 77.1 %; mass change in the range from 360 to 600 °C: -9.2 %). No significant mass loss occurred due to purging. The course of the thermogravimetric curve suggests decomposition of the test item. After cooling the residue looked black and shiny. The DSC measurements were performed twice in the temperature range from 20 - 400 °C. A sharp endothermic peak indicating a melting point could be observed (peak maximum: 119 °C /119 °C; extrapolated onset temperature: 115.20 °C/ 115.22 °C; rounded mean of both determinations: 115 °C). Upon further heating the DSC-curve showed no more sharp peaks but the typical fluctuating course of decomposition starting at approx. 180 °C. Reweighing after the measurement showed that the sample had lost 74.7 %/ 74.8 % of its mass. The residue was brown-black discoloured and bloated coming out of the 50 µm hole.

Conclusions:
The melting temperature of 2-oxoglutaric acid was determined by differential scanning calorimetry according to OECD Test Guideline 102 and EU test method A.1
The melting temperature is 115 °C.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2016
Report Date:
2016

Materials and methods

Test guideline
Qualifier:
no guideline followed
Principles of method if other than guideline:
Visual observation of appearance and physical state was reported during determination of melting point according to OECD guideline 102, GLP.
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder

Results and discussion

Physical state at 20°C and 1013 hPa:
solid
Form / colour / odour
Key result
Form:
solid: particulate/powder
Colour:
yellowish
Odour:
other: nearly odourless

Applicant's summary and conclusion

Conclusions:
During the determination of melting point according to OECD Guideline 102, it was reported that 2-oxoglutaric acid is a solid/powder at ambient temperature.