Nickel oxalate

Boiling point

Administrative data

Endpoint:

boiling point

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Peer-reviewed publication that is well-documented.

Data source

Reference

Reference Type:

publication

Title:

Kinetics of thermal decomposition of nickel oxalate dihydrate in air

Author:

Zhan D, Cong C, Diakite K, Tao Y and Zhang, K

Year:

2005

Bibliographic source:

Thermochimica Acta 430: 101-105

Materials and methods

GLP compliance:

not specified

Type of method:

other: The thermal decomposition of nickel oxalate dihydrate in air was investigated by thermal analysis measurements (TG, DTG, DTA) and differential scanning calorimetry. X-ray powder diffraction was used to identify the decomposition product(s).

Test material

Test material information

Constituent 1

Reference substance name:

nickel (II) oxalate dihydrate

IUPAC Name:

nickel (II) oxalate dihydrate

Constituent 2

Reference substance name:

6018-94-6

Cas Number:

6018-94-6

IUPAC Name:

6018-94-6

Details on test material:

- Name of test material (as cited in study report): nickel oxalate dihydrate
- Molecular formula (if other than submission substance): NiC2O4.2H2O
- Molecular weight (if other than submission substance): 182.7 g/mol
- Physical state: no data
- Analytical purity: no data
- Lot/batch No.: no data
- Stability under test conditions: no data
- Storage condition of test material: no data

Results and discussion

Boiling point

Boiling pt.:

> 365 °C

Decomposition:

yes

Decomp. temp.:

>= 258 - <= 365 °C

Remarks on result:

other: The test substance underwent an initial decomposition at 258 deg C (endothermic) and a complete decomposition at 365 deg C (exothermic).

Any other information on results incl. tables

DTA peaks closely corresponded to the weight changes observed on the TG curves. The curves showed that the thermal decomposition of the test substance below 500 deg C occurs in two well-defined steps. The first step is from 196 to 284 deg C, characterized by a endothermic peak at 258 deg C in accordance with calculated weight loss of 19.73%, attributed for the dehydration of nickel oxalate dihydrate and formation of anhydrous oxalate. The anhydrous oxalate is stable up to 316 deg C, and then decomposed in the second step. This step shows an exothermic process with DTA peak at 365 deg C, indicating a weight loss of 39.85% due to the decomposition of nickel oxalate and the formation of NiO (the decomposition product NiO was identified through X-ray diffraction). The exothermic character of the DTA peak accompanying the oxalate decomposition step is due to the air oxidation of CO to CO2 , which is the common fact in thermal decomposition of metal oxalate in air.

Applicant's summary and conclusion

Conclusions:

Nickel oxalate dihydrate was shown to undergo thermal decomposition in a two-step process. The first decomposition is from 196 to 284 deg C and is characterized by a endothermic peak at 258 deg C. This step involves the dehydration of nickel oxalate dihydrate and formation of anhydrous oxalate. The second step shows an exothermic process with a DTA peak at 365 deg C due to the decomposition of nickel oxalate and the formation of NiO. Therefore, the test substance decomposed before the boiling temperature was reached.