Zirconium dichloride oxide

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

27 May - 22 June 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

yes

Remarks:

Deviations from standard method due to readily and high solubility of the test item

GLP compliance:

yes (incl. QA statement)

Type of method:

other: Due to the high water solubility as determined in the pretest, no main study was performed.

Water solubility:

> 1 000 g/L

Temp.:

20 °C

pH:

0.05

Details on results:

The pH of sample 10 was inconsistently high. Sample solutions generated during the water solubility test were stable, without any significant precipitation of insoluble zirconium oxide hydrolysis product. This was attributed to the acidic nature of the sample solutions, in that rapid, but only limited hydrolysis occured on dissolution, resulting in an acidic solution pH at which the parent test item was both soluble and more critically, stable.

During the second experiment, investigating the reactivity with water, a precipitate was observed after neutralisation of the sample and the total dissolved zirconium concentration was demonstrated by ICP-MS to have reduced drastically. These results were consistent with data from literature. Hydrolysis of ZrOCl2 is recognised as being incomplete in the presence of hydrochloric acid, with the formation of a stable zirconium oxychloride intermediate, not the anticipated oxide.

Conclusions:

Based on the outcome of the study the test item is considered highly soluble (miscible at a 1 to 1 ratio), and by limited hydrolysis generating hydrochloric acid and thus acidifying the sample solution, a stable equilibrium is reached. On neutralisation of the solution, the hydrochloric acid is consumed, the eliquibrium disrupted and hydrolysis is able to continue towards completion. The zirconium content of the solution is lost through precipitation, most probably as the proposed insoluble hydrolysis product zirconium dioxide.

Reference 2

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Reason / purpose for cross-reference:

reference to same study

Principles of method if other than guideline:

Data in this peer-reviewed publication were taken from many sources, including both compilations and primary literature. Where conflicts were found, the value deemed most reliable was chosen for inclusion in the handbook. Reference sources were not provided for this parameter, nor was the experimental method.

GLP compliance:

not specified

Remarks on result:

other: The test substance is very soluble in water

Details on results:

It was reported that the test substance was very soluble in water and alcohol.

Conclusions:

Under the test conditions it was reported that the test substance was very soluble in water and alcohol.

Reference 3

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Reason / purpose for cross-reference:

reference to same study

Principles of method if other than guideline:

Data in this peer-reviewed publication were taken from many sources, including both compilations and primary literature. Where conflicts were found, the value deemed most reliable was chosen for inclusion in the handbook. Reference sources were not provided for this parameter, nor were the experimental methods.

GLP compliance:

no

Remarks on result:

other: The test substance is very soluble in water

Details on results:

It was reported that the test substances was very soluble in water.

Conclusions:

Under the test conditions it was reported that the test substance was very soluble.

Reference 4

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

no data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Principles of method if other than guideline:

Data in this peer-reviewed publication were taken from many sources, including both compilations and primary literature. Where conflicts were found, the value deemed most reliable was chosen for inclusion in the handbook. Reference sources were not provided for this parameter, nor were the experimental methods.

GLP compliance:

no

Remarks on result:

other: The test substance is freely soluble in water

Details on results:

It was reported that the test substance was freely soluble in water.

Conclusions:

Under the test conditions it was reported that the test substance is freely soluble in water.

Description of key information

The water solubility of zirconium dichloride oxide was determined following a pre-test of the EC A.6 test method to be very soluble (miscible at a 1 to 1 ratio) at 20 °C (O'Connor and Woolley, 2010). This study was considered as the key study.

Additional information

The key study was the study of O'Connor and Woolley (2010). In this study zirconium dichloride oxide was determined to be miscible with water at a 1 to 1 ratio. When dissolving zirconium dichloride oxide, hydrochloric acid is generated, acidifying the sample solution and establishing a stable equilibrium. On neutralisation of the solution, the hydrochloric acid is consumed, the equilibrium disrupted and hydrolysis is able to continue towards completion. The zirconium content of the solution is lost through precipitation, most probably as the insoluble hydrolysis product zirconium dioxide.

The concluded high solubility from the study was supported by peer-reviewed data from three handbooks indicating zirconium dichloride oxide to be very soluble in water (Lewis, 1992; Lide, 2001; O'Neil, 2006).