Dicopper sulphide

Stability: thermal, sunlight, metals

Administrative data

Endpoint:

stability: thermal, sunlight, metals, other

Remarks:

Migrated from section 'Stability: thermal, sunlight, metals'

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Well-reported study conducted in accordance with sound scientific principles.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2011

Report date:

2011

Materials and methods

Principles of method if other than guideline:

With the differential scanning calorimetry (DSC) method, the heat flow between the (filled) sample crucible and a reference crucible (filled with an inert material or left empty) is measured as a function of the oven temperature and of time. From the recorded heat-flow/time signal the enthalpy of the decomposition reaction (endothermic or exothermic) can be determined. The so-called onset temperature marks the beginning of a thermal effect under the chosen heating conditions. In order to find the onset temperature using the DSC software the program uses a tangent on the steepest slope of a peak (thermal effect) which determines the onset temperature by the resulting osculation point to the extrapolated base line. During a test the sample is enclosed in a hermetically sealed stainless steel crucible (high pressure type). The crucible is filled with the sample in a nitrogen atmosphere. DSC apparatus Type 131 (SETARAM) was used for the tests. Each test run was conducted with a heating rate of 5 K/min between 30 °C and 500 °C using hermetically sealed gilded stainless steel crucibles to avoid evaporation. Uncertainty of results at the chosen rate of 5 K/min (obtained from runs with calibration substances): Enthalpy ± 5 %, Temperature ± 2 K.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Dicopper sulphide

EC Number:

244-842-9

EC Name:

Dicopper sulphide

Cas Number:

22205-45-4

Molecular formula:

Cu2S

IUPAC Name:

Copper(I) sulphide

Details on test material:

- Name of test material (as cited in study report): Copper (I) sulfide.
- Test material purity: Not given.
- Lot/batch No.: Shelflife 2011-07.

Results and discussion

Any other information on results incl. tables

Under the given test conditions a first exothermic reaction could be seen at about 130 °C. The reaction enthalpy was −70.9 J/g. A second exothermic reaction, which nearly directly followed the first reaction, was observed at about 355 °C. The enthalpy of this reaction was −49.2 J/g. In the case of nearly consecutive exothermic reactions the enthalpy sum of both reactions should be considered in a worst case scenario. The enthalpy sum is −120.1 J/g.

Applicant's summary and conclusion

Conclusions:

The DSC test showed a decomposition energy of <−300 J/g (exotherm). Copper (I) sulfide is therefore considered to be thermally stable.