Registration Dossier

Diss Factsheets

Physical & Chemical properties

Endpoint summary

Administrative data

Description of key information

Additional information

Discussion of physicochemical properties of whole substance

The substance is a complex mixture of hydrocarbons with carbon numbers in the range C11 to C16. It is a liquid at standard temperature and pressure, with measured boiling range 212-258°C, measured relative density of 0.7627 at 20±0.5°C and measured kinematic viscosity values of 2.4 mm²/s at 25ºC and 1.8 mm²/s at 40ºC. It is not considered to be surface active based on structural examination.

 

The substance is not classified as for flammability according to Regulation (EC)No. 1272/2008 on the basis of measured flash point of >61°C and a measured boiling range of 212.1 -258.2°C at 101.8 kPa. The auto-ignition temperature is in the range 200 - 212°C based on read-across from related substances. Based on its chemical structure and experience in handling and use it is not considered to exhibit explosive or oxidising properties or be flammable in contact with air or moisture.

 

No measured data are available for the registered substance itself for the following endpoints: melting point; vapour pressure; n-octanol/water partition coefficient and water solubility. Data gaps for these endpoints are filled using a weight of evidence approach based on reliable measured data for other Fischer-Tropsch process-derived hydrocarbons containing overlapping carbon number ranges (Hydrocarbons, C10-C13, n-alkanes, isoalkanes, <2% aromatics (GS190), Hydrocarbons, C12-C15, n-alkanes, isoalkanes, <2% aromatics (GS215), Hydrocarbons, C14-C16, n-alkanes, isoalkanes, <25 aromatics (GS250) and Hydrocarbons, C15-C19, n-alkanes, isoalkanes, <2% aromatics (GS270)).

 

Measured pour point values, determined according to ASTM D 5950/ISO 2016, were <-20°C for all substances, therefore it can be concluded that the pour point of Hydrocarbons, C11-C16, n-alkanes, isoalkanes, <2% aromatics is also <-20°C.

 

In all cases, measured whole-substance water solubility was determined to be <0.1 mg/l and it can therefore be concluded that the water solubility of Hydrocarbons, C11-C16, n-alkanes, isoalkanes, <2% aromatics is also <0.1 mg/l.

 

Measured whole-substance vapour pressure values were in the range 0.04 to 34 Pa for substances covering the carbon number range C10 to C19, therefore it is expected that the whole-substance vapour pressure of Hydrocarbons, C11-C16, n-alkanes, isoalkanes, <2% aromatics would be within this range.

 

n-Octanol/water partition coefficient studies using the OECD 117 HPLC method gave measured log Kow values in the range 5.57 to >7.2 for constituents of hydrocarbons in the range C10 to C19; individual structures were not identified.

 

In addition to measured data, key physicochemical properties of individual constituents of the registered substance were predicted using validated QSAR or calculation methods, as described below.

Physicochemical properties of constituents

For the purposes of the Chemical Safety Assessment, Hydrocarbons, C9-C11, n-alkanes, isoalkanes, <2% aromatics (GS1927) has been assessed using the PETRORISK model. The Petrorisk model for GS 1927 is attached in Section 13.2 of the IUCLID dossier.

As supporting information, predicted property data for vapour pressure, water solubility, n-octanol/water partition coefficient (log Kow) and Henry’s Law constant (HLC) were obtained for the constituents using separately validated Quantitative Structure Activity Relationships (QSARs), as described below.

 

Partition coefficient

The individual constituents of the substance have predicted log Kow values of 5.11 to 9.18 at 20°C using a validated QSAR estimation method. Further details about the prediction are in the QMRF and QPRF attached to the IUCLID dossier.

 

Water solubility

The individual constituents of the substance have predicted water solubility values of <1E-04 to 1.5E-01 mg/l at 20°C. Therefore, the constituents are considered insoluble in water on the basis of available predicted results. Further details about the prediction are in the QMRF and QPRF attached to the IUCLID dossier.

 

Vapour pressure

The individual constituents of the substance have predicted vapour pressure values of 3.4E-02 Pa to 330 Pa at 25°C using a validated QSAR estimation method. Further details about the prediction are in the QMRF and QPRF attached to the IUCLID dossier.

 

Henry’s Law Constant (HLC)

Values can be calculated from the other physicochemical properties using the expression:

HLC (Pa.m3/mol) = [VP (Pa) x MW (g/mol)] ÷ [WS (mg/l)]

 

Where:

VP = vapour pressure; MW = molecular weight; WS = water solubility

 

Summary of relevant properties of constituents

The data are summarised in the table below.

 

Table: Predicted physicochemical properties for constituents of Hydrocarbons, C11-C16, n-alkanes, isoalkanes, <2% aromatics

Carbon

Number

CH3

CH2

branched

Vapour pressure (Pa) at 25°C

log Kow

Water solubility at 20°C (mg/l)

10

2

8

0

2.61E+02

5.25

1.0E-01

11

2

9

0

8.53E+01

5.74

3.2E-02

12

2

10

0

2.79E+01

6.23

9.7E-03

13

2

11

0

9.14E+00

6.73

3.0E-03

14

2

12

0

2.99E+00

7.22

9.0E-04

15

2

13

0

9.79E-01

7.71

2.7E-04

16

2

14

0

3.21E-01

8.20

8.2E-05

17

2

15

0

1.05E-01

8.69

2.4E-05

18

2

16

0

3.44E-02

9.18

7.3E-06

10

3

6

1

3.27E+02

5.18

1.2E-01

11

3

7

1

1.07E+02

5.67

3.8E-02

12

3

8

1

3.51E+01

6.16

1.2E-02

13

3

9

1

1.15E+01

6.65

3.6E-03

14

3

10

1

3.76E+00

7.14

1.1E-03

15

3

11

1

1.23E+00

7.63

3.3E-04

16

3

12

1

4.03E-01

8.13

9.9E-05

17

3

13

1

1.32E-01

8.62

2.9E-05

18

3

14

1

4.32E-02

9.11

8.8E-06

10

3

5

2

3.06E+02

5.11

1.5E-01

11

3

6

2

1.00E+02

5.60

4.6E-02

12

3

7

2

3.28E+01

6.09

1.4E-02

13

3

8

2

1.07E+01

6.58

4.3E-03

14

3

9

2

3.52E+00

7.07

1.3E-03

15

3

10

2

1.15E+00

7.56

4.0E-04

16

3

11

2

3.77E-01

8.05

1.2E-04

17

3

12

2

1.23E-01

8.54

3.6E-05

18

3

13

2

4.04E-02

9.03

1.1E-05