potassium titanium oxide (K2Ti6O13)

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:

Testing was conducted between 14 January 1999 and 4 May 1999.

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

GLP compliance:

yes (incl. QA statement)

Remarks:

Date of inspection: 23/03/1998 Date of signature: 21/07/1998

Type of method:

flask method

Key result

Water solubility:

< 0.452 mg/L

Temp.:

20 °C

pH:

6.2

Remarks on result:

other: Flask method.

Water solubility:

< 0.24 mg/L

Temp.:

25 °C

Remarks on result:

other: Visual estimation at room temperature.

Conclusions:

Interpretation of results (migrated information): slightly soluble (0.1-100 mg/L)
The water solubility was determined to be less than 4.52 x 10-4 g/I of solution at 20.0 ± 0.5· C, using the flask method, Method A6 of Commission Directive 92/69/EEC.
By visual estimation, the water solubility was found to be less than 2.40 x 10-4 g/l.

Executive summary:

The water solubility was determined to be less than 4.52 x 10^-4 g/L of solution at 20.0 ± 0.5· C, using the flask method, Method A6 of Commission Directive 92/69/EEC.

By visual estimation, the water solubility was found to be less than 2.40 x 10-4 g/l.

Reference 2

Endpoint:

water solubility

Type of information:

read-across from similar mixture/product

Adequacy of study:

key study

Study period:

10th - 19th December 2012

Reliability:

2 (reliable with restrictions)

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

Principles of method if other than guideline:

- SOP 061.00 Issue No. 6 Expires November 2013 with quantitative measurement by ICP-OES, SOP 025.04 Issue 8 Expires March 2014.

GLP compliance:

no

Type of method:

flask method

Water solubility:

1.4 mg/L

Temp.:

25 °C

Remarks on result:

other: No pH data.

- ICP-OES Results: See Table in attached report

 

- Calculations: The concentration of Potassium and Titanium (mg/I) in each test solution is calculated from the calibration graph using the ICP-OES software.

 

- Standard Recoveries: Standard recoveries of between 90 -110% for Potassium and Titanium were observed, which are acceptable for analysis at the levels being analysed.

 

- Treatment of Results:

 

Timepoint	K mg/L w/v	Ti mg/L w/v
1 Day	59	0.7
2 Days	71	0.8
3 Days	70	0.6
4 Days	77	0.8
5 Days	85	0.7

 

For potassium, the solubility does appear to increase with time and the guidelines state repeatability should be <15%. Use of Day 3 to Day 5 results are within the acceptance criteria and therefore the mean of the test 3, 4, and 5 results will be used to calculate the quoted water solubility result. For titanium, there is no clear indication of the solubility changing with time, although at the concentration being observed, it would be difficult to assess. As for potassium, the mean of the test 3, 4, and 5 results will be used to calculate the quoted water solubility result.

 

Mean of tests 3, 4 and 5 (Total mg/L w/v) 77 mg/I Potassium

 

Mean of tests 3, 4 and 5 (Total mg/L w/v) 0.7 mg/l Titanium

 

The titanium content needs to be amended to take into account the composition of the test substance, K₂Ti₆O₁₃.

 

Molecular weight K = 38.10

Molecular weight Ti = 47.88

Molecular weight O = 16.00

 

Molecular weight K₂Ti₆O₁₃= 573.5

Molecular weight Ti₆= 287.3

 

Therefore 0.7 mg/L Titanium x (573.5/287.3) = 1.4mg/L Potassium Hexatitanate

 

The potassium content needs to be amended to take into account the composition of the test substance, K₂Ti₆O₁₃.

 

Molecular weight K = 38.10

Molecular weight Ti = 47.88

Molecular weight O = 16.00

 

Molecular weight K₂Ti₆O₁₃= 573.5

Molecular weight K₂ = 76.2

 

Therefore 77 mg/L Potassium x (573.5/76.2) = 580mg/L Potassium Hexatitanate

 

The lower values observed for titanium are presumed to reflect the solubility of the test substance Potassium Hexatitanate. The higher concentration of potassium observed may be due to solubte potassium salts in the test substance. A trace amount of soluble potassium salt such as potassium chloride or sulphate in the test substance could result in a significant increase in the potassium content at the levels being observed. The water solubility of Potassium Hexatitanate will be reported as 1.4mg/L. The pH of the aqueous solutions was measured after completion of the tests.

- Individual results:

 

Test	pH of solution
1	7.63
2	7.65
3	7.65
4	7.87
5	7.87
Water blank	7.89

 

Mean pH of tests 3, 4 and 5 = 7.8

Conclusions:

Interpretation of results (migrated information): slightly soluble (0.1-100 mg/L)
- Report:
ASG: 10462612
Water Solubility at 25°C ± 1°C (mg/L): 1.4
Purity of Potassium Hexatitanate was determined by sponsor to be >99% (Batch 180215)

Executive summary:

- Analysts: Joe Wicks (Shake flask Procedure) and Dale Mortimer (ICP-OES Analysis)

- Techniques/lnstrumentation/Test Method Ref/Test Specification Ref:

   - Water Solubility in accordance with EU A6 Regulation (EC) No 440/2008, Annex, Official Journal of the European Union, Shake Flask Method.

   - SOP 061.00 Issue No. 6 Expires November 2013 with quantitative measurement by ICP-OES, SOP 025.04 Issue 8 Expires March 2014.

- Instrument: Perkin-Elmer Optima 3300 ICP-OES LIMS 0792D (PQ Due: May 2013)

- The data contained in this report has been generated in a laboratory holding a current statement of GLP Compliance, issued by the UK GLP Monitoring Authority, MHRA, but not as part of a formal GLP study.

 

- Report:

 

ASG	Water Solubility at 25°C ±1°C (mg/L)
10462612	1.4

 

Purity of Potassium Hexatitanate was determined by sponsor to be >99% (Batch 180215)

Description of key information

The water solubility of the substance ranges between < 0.454 and 1.4 mg/L at 20 -25 °C.

Key value for chemical safety assessment

Water solubility:

1.4 mg/L

at the temperature of:

25 °C