Alcohols, C12-13, branched and linear, ethoxylated

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

20 Feb - 18 Mar 2015

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

GLP compliance:

yes

Type of method:

static method

Temp.:

20 °C

Vapour pressure:

6 Pa

Remarks on result:

other: Mean of Runs 4 and 5. For transition data, see Any other information on results incl. tables.

Temp.:

20.6 °C

Vapour pressure:

0.81 Pa

Remarks on result:

other: direct measurement, see Any other information on results

Full test results:

Run 1:

Temperature/K	Pressure/Pa
302.15	60
313.35	90
324.45	160
333.55	210
343.15	340
353.05	480
364.65	700

Extrapolated value at 293.15 K (20 °C): 36 Pa

Run 2:

Temperature/K	Pressure/Pa
312.75	210
324.35	330
331.85	440
333.55	210
345.45	650
354.65	850
364.55	1150

Extrapolated value at 293.15 K (20 °C): 98 Pa

Run 3:

Temperature/K	Pressure/Pa
301.55	30.56
313.45	58.38
323.35	78
331.65	100.31
341.35	130
354.15	190
361.85	240

Extrapolated value at 293.15 K (20 °C): 24 Pa

Run 4:

Temperature/K	Pressure/Pa
302.85	10.35
312.85	36.55
323.35	78
322.65	67.53
333.45	150
343.05	190
351.55	250
363.15	360
374.95	480

Extrapolated value at 293.15 K (20 °C): 9 Pa

Run 5:

Temperature/K	Pressure/Pa
293.75	0.81
303.95	11.82
313.35	22.46
323.75	33.9
332.25	42.01
345.15	70.46
351.85	91.37
364.35	160

Extrapolated value at 293.15 K (20 °C): 3 Pa

Runs 1 -3 remark: The sample was shaken before use such that the small amount of white, settled, solid was evenly distributed throughout the sample.

Run 4 remark: The sample was shaken before use such that the small amount of white, settled, solid was evenly distributed throughout sample. Sample was degassed overnight with stirring.

Run 5 remark:

The sample was shaken before use such that the small amount of white, settled, solid was evenly distributed throughout sample. Sample was degassed overnight with stirring. During testing the sample became a clear colourless solution. Upon cooling overnight the sample returned to a cloudy solution.

Comments:

Five vapour pressure experiments were carried out in total. Runs 1 to 3 gave higher pressure readings than expected. It was initially suspected that the sample needed either a longer time or a more efficient way to de-gas. Two further analyses were conducted using a magnetic stirrer to aid the degassing overnight. During the analysis a phase change was observed as the suspended particles went into solution. This was conformed in the data obtained.

As per the EC440/2008 test protocol, when phase change is observed during the analysis, the temperature at which the phase change was observed (i.e. 39.7 °C and 60.3 °C in Run 4; and 30.8 °C and 40.2 °C in Run 5), then 10 °C and 20 °C above and below the phase transitions temperatures shall be reported. Due to the starting temperatures used in runs 4 and 5 it is not possible to report the vapour pressure results for a temperature 20 °C below the phase change.

The results of testing are highly dependent on the composition and physical nature of the sample. In dust explosion testing, for example, the particle size distribution, moisture content, particle shape and preparation method can all markedly affect results. For this reason, any change in manufacturing/handling procedures or composition should be accompanied by a review of the relevant data.

Due to the nature of the sample and the fact that one of the components of the test item undergoes phase change the results of testing should be used with caution and are suspected to be high. A direct measurement at 20.6°C during test Run 5 of 0.81 Pa should be taken into consideration.

Description of key information

6 Pa at 20 °C (EU A.4, static method)

0.81 Pa at 20.6 °C (direct measurement)

Additional information

Due to the nature of the sample and the fact that one of the components of the test item undergoes phase change the results of testing should be used with caution and are suspected to be high (three first test runs were discarded). A direct measurement at 20.6 °C during test Run 5 of 0.81 Pa can be taken into consideration.