2-propanol and 2-butanol production, distn. residues

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

6 September 2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Fully documented study run under GLP and according to international guidelines.

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

static method

Key result

Temp.:

20 °C

Vapour pressure:

7 263 Pa

Temp.:

25 °C

Vapour pressure:

9 273 Pa

Transition / decomposition:

no

Table 1        Measurement Values

1. Determination increasing temperature		2. Determination decreasing temperature
Temp. in °C	Pressure in hPa	Temp. in °C	Pressure in hPa
20.8	74.4	51.7	303.2
24.4	88.6	42.5	208.5
27.4	103.5	37.6	169.3
29.1	113.0	33.6	140.6
33.4	138.8	29.6	115.8
33.0	136.0	26.2	97.9
41.6	199.4	23.6	86.2
46.9	246.3	22.1	80.2
54.5	328.8	-	-
54.6	331.0	-	-

 

From the measured values for the increasing and for the decreasing temperature, log P and 1/T were calculated and log P (in log Pa) against 1/T (in 1/K) was plotted.

The regression curve with slope B, intercept A and correlation r was calculated. From the values of these parameters, vapour pressures at 20.0 °C and at 25.0 °C were calculated with: Log P = (B * 1/T) + A.

The parameters for the linear regression of the values are presented in the following table:

Table 2     Linear Regression Parameters

Parameter	Value
Slope	-1854.550616
Intercept	10.18740179
Correlation coefficient r	-0.999644229

 

Using the equation which is stated in chapter 8.2, vapour pressure at ambient temperature and boiling point were calculated as:

Table 3     Calculated Values for Vapour Pressure

Parameter	Value	Unit
Vapour Pressure (20 °C)	7263	Pa
Vapour Pressure (25 °C)	9273	Pa

 

Conclusions:

Vapour pressures of 7263 Pa at 20 °C and 9273 Pa at 25 °C were determined for reaction mass of 2,2'-oxybisbutane (DSBE), DIPE, SBA and 2-methylpropan-2-ol (TBA).

Executive summary:

The vapour pressure of reaction mass of 2,2'-oxybisbutane (DSBE), DIPE, SBA and 2-methyl­propan-2-ol (TBA) was determined using the static method.

Vapour pressures of 7263 Pa at 20 °C and 9273 Pa at 25 °C were determined.

These values were calculated from the regression of 18 individual measurements.

Description of key information

Vapour pressures of 7263 Pa at 20 °C and 9273 Pa at 25 °C were determined.

Key value for chemical safety assessment

Vapour pressure:

7 263 Pa

at the temperature of:

20 °C

Additional information

The vapour pressure of the test item reaction mass of 2,2'-oxybisbutane (DSBE), DIPE, SBA and 2-methylpropan-2-ol (TBA) being a representative sample for "2-propanol and 2-butanol production, distn. residues" was calculated as 7263 Pa at 20.0 °C, and 9273 Pa at 25 °C. These values show good correspondence with the measured values in this temperature range: at 20.4 °C, 7440 Pa were measured, at 24.4 °C 8860 Pa and at 26.2 °C, 9790 Pa were measured.

No deviations between the measured values at increasing and at decreasing temperatures were detected. No observations were made which might cause doubts concerning the validity of the study outcome and therefore the study is considered valid.