Dipraseodymium dizirconium heptaoxide

Auto flammability

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

relative self-ignition temperature (solids)

Type of information:

experimental study

Adequacy of study:

weight of evidence

Study period:

17 July 2012 - 21 January 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.16 (Relative Self-Ignition Temperature for Solids)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks on result:

other: The test material has been determined not to have a self-ignition temperature below 400°C.

The test material was a brown powder. Whilst heating, the sample showed no significant temperature rise above the oven temperature. On completion of the test, the cube remained full of brown powder.

Conclusions:

The test material has been determined not to have a self-ignition temperature below 400°C.

Reference 2

Endpoint:

relative self-ignition temperature (solids)

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Justification for type of information:

Data available on the individual constituents of the reaction mass were considered to conclude on the endpoint. For praseodymium(III,IV) oxide, an experimental study is available, which is used for read across. For zirconium dioxide no data are available on the endpoint, because there was no need for performing an experimental study (study waived, see further). The read across justification document is attached to IUCLID Section 13.

Reason / purpose for cross-reference:

read-across source

Remarks on result:

other: The reaction mass of praseodymium(III,IV) oxide and zirconium dioxide is not considered to be autoflammable.

Remarks:

This conclusion is based on two types of information. First, the results of an experimental study performed with praseodymium(III,IV) oxide according to the EU A.16 guideline demonstrated that praseodymium(III,IV) oxide has no self-ignition temperature when heated up to 400°C. Second, zirconium dioxide is concluded not to be autoflammable either, based on the fact that inorganic oxides in which the element is in its highest possible oxidation state are incapable of further reaction with oxygen, which is the case for zirconium dioxide (zirconium in oxidation state +IV). Consequently, the reaction mass of these two oxides can safely be concluded not to be autoflammable either.

Description of key information

No experimental data is available on the autoflammability of dipraseodymium dizirconium heptaoxide. However, based on information on the individual constituents of the substance, it can be concluded that the substance is not autoflammable. This conclusion is based on two types of information. First, the results of an experimental study performed with praseodymium(III,IV) oxide according to the EU A.16 guideline demonstrated that praseodymium(III,IV) oxide has no self-ignition temperature when heated up to 400°C. Second, zirconium dioxide is concluded not to be autoflammable either, based on the fact that inorganic oxides in which the element is in its highest possible oxidation state are incapable of further reaction with oxygen, which is the case for zirconium dioxide (zirconium in oxidation state +IV). Consequently, the substance composed of these two oxides can safely be concluded not to be autoflammable either.

Additional information

1. Information on praseodymium(III,IV) oxide

Based on a guideline study (White, 2013; Klimisch 1), praseodymium(III,IV) oxide has been determined to have no self-ignition temperature below 400°C.

2. Information on zirconium dioxide

Zirconium dioxide is an inorganic oxide in which zirconium is in its highest possible oxidation state (+IV) and is therefore incapable of further reaction with oxygen. Based on this information, zirconium dioxide is concluded not to be autoflammable.

3. Conclusion on the substance dipraseodymium dizirconium heptaoxide

Given that the substance is composed of praseodymium(III,IV) oxide and zirconium dioxide, above mentioned information allows concluding that the substance dipraseodymium dizirconium heptaoxide is not autoflammable either.