Shale oils

Surface tension

Link to relevant study record(s)

Reference

Endpoint:

surface tension

Type of information:

experimental study

Adequacy of study:

key study

Study period:

17th June - 2nd September 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results.

Qualifier:

according to guideline

Guideline:

OECD Guideline 115 (Surface Tension of Aqueous Solutions)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.5 (Surface Tension)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

ring method

Key result

Surface tension:

59.3 mN/m

Temp.:

20 °C

Conc.:

90 other: % of saturation concentration

The calibration factor φ_b was determined to be 1.0466 for double distilled water. Table 1 shows the individual measurements for the surface tension of the aqueous test item solution. From these, the mean and the corrected value for the given solution were calculated and shown in the same table. The tabulated values represent rounded results obtained from calculation using the exact raw data.

Table 1: Determination of Surface Tension for the Test Item Solution

Time expired     [hours:min]	Temperature     [ºC]	Surface Tension [mN/m]
		measured	Mean value calculated from the bold values (σ*)	Mean value corrected for calibration (σ1)	σ1corrected for Harkins-Jordan (σ)
First sample
00:30	20.0	57.2	57.02	59.67	58.76
00:32	20.0	57.2
00:33	20.0	57.2
00:35	20.0	56.8
00:36	20.0	56.8
00:37	20.0	56.8
Second sample
00:33	20.0	58.4	57.98	60.69	59.86
00:35	20.0	58.2
00:36	20.0	58.0
00:38	20.0	57.9
00:39	20.0	57.8
00:41	20.0	57.6

Mean value from both samples: σ = 59.3 mN/m

with

σ* . φ_b = σ₁

φ_b = calibration factor = 1.0466

and

σ₁ . F_c = σ

F_c = factor for correction acc. to Harkins-Jordan

= 0.985 for 59.67 mN/m and 0.986 for 60.69 mN/m

Conclusions:

In conclusion, the surface tension of Shale Oil middle fraction in water (90 % of saturation concentration) was determined to be 59.3 mN/m at 20.0°C.
Based on the criteria as outlined in the EEC Guideline, Shale Oil is a surface active substance.

Executive summary:

The surface tension of shale oil middle fraction was measured using the ring method in accordance with the standardised guidelines OECD 115 and EU Method A.5, under GLP conditions.

Under the conditions of the study, the surface tension of Shale Oil in water (90 % of saturation concentration) was determined to be 59.3 mN/m at 20.0°C.

Based on the criteria as outlined in the EEC Guideline, Shale Oil is a surface active substance.

Description of key information

The surface tension of Shale Oil middle fraction in water (90 % of saturation concentration) was determined to be 59.3 mN/m at 20.0°C.
Based on the criteria as outlined in the EEC Guideline, Shale Oil is a surface active substance.

Key value for chemical safety assessment

Surface tension:

59.3

Additional information

The surface tension of shale oil middle fraction was measured using the ring method in accordance with the standardised guidelines OECD 115 and EU Method A.5, under GLP conditions. The study was awarded a reliability score of 1 in accordance with the criteria set forth by Klimisch et al. (1997).

Under the conditions of the study, the surface tension of Shale Oil in water (90 % of saturation concentration) was determined to be 59.3 mN/m at 20.0°C.

Based on the criteria as outlined in the EEC Guideline, Shale Oil is a surface active substance.