2-Chloro-5-chloromethylpyridine

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

GLP compliance:

yes (incl. QA statement)

Type of method:

other: dynamic method + vapor pressure balance

Temp.:

20 °C

Vapour pressure:

0.17 Pa

Temp.:

25 °C

Vapour pressure:

0.4 Pa

Temp.:

50 °C

Vapour pressure:

11 Pa

The vapour pressure was at first measured in the temperature range of 21 °C to 31 °C by Effusion Method (Vapour Pressure Balance). The course of the vapour pressure show a broad scatter. From these data points it is concluded, that the measured vapour pressure is mainly influenced by volatile by-products, which are available in the test item only in limited quantities.

An additional measurement with the dynamic method was performed.

The Antoine constants from the regression of all data from both methods (vapour pressure balance and dynamic method) were used to calculate the vapour pressure for 20, 25 and 50 °C.

Conclusions:

The vapour pressure of 2-chloro-5-chloromethylpyridine at 20°C was determined as 0.17 Pa and at 25°C as 0.4 Pa.

Executive summary:

A study was conducted to assess the vapour pressure of 2 -chloro-5-chloromethylpyridine according to EU test method A.4 which is equal to OECD test guideline 104. The effusion method (vapour pressure balance) and the dynamic method were used for the determination.

Vapour Pressure Balance (Effusion Method)

The apparatus consists of a high vacuum chamber. The test item is filled into a furnace in the chamber from which the sample evaporates. The temperature of the ceil with the test item is controlled by a surrounding heater. The vapour forms a molecular jet of defined geometry limited by an orifice. The vapour jet is condensed on a plate cooled down below - 100 °C by a surrounding copper baffle which is in contact with liquid nitrogen. The plate forms one end of an ultra micro balance.

The pressure of the test item is calculated from the weight increase during an elapsed time period.

The vapour pressure was at first measured in the temperature range of 21 °C to 31 °C by Effusion Method (Vapour Pressure Balance). The course of the vapour pressure show a broad scatter. From these data points it is concluded, that the measured vapour pressure is mainly influenced by volatile by-products, which are available in the test item only in limited quantities.

An additional measurement with the dynamic method was performed.

Vapour Pressure (Dynamic Method)

The vapour pressure is measured by determining the boiling point of the test item at various specified pressures between roughly 10 and 1000 hPa.

Before filling the test apparatus the whole equipment was flooded with nitrogen to minimize the presence of oxygen. After filling the apparatus with the test item the lowest desired pressure is set and the heating system is switched on. Equilibrium is reached when a constant boiling temperature is achieved at a given pressure. After recording this point the pressure is increased step by step and up to the boiling point.

The Antoine constants from the regression of all data from both methods (vapour pressure balance and dynamic method) were used to calculate the vapour pressure for 20, 25 and 50 °C, which were 0.17, 0.4 and 11 Pa respectively.

Description of key information

A study was conducted to assess the vapour pressure of 2 -chloro-5-chloromethylpyridine according to EU test method A.4 which is equal to OECD test guideline 104. The effusion method (vapour pressure balance) and the dynamic method were used for the determination.

Vapour Pressure Balance (Effusion Method)

The apparatus consists of a high vacuum chamber. The test item is filled into a furnace in the chamber from which the sample evaporates. The temperature of the ceil with the test item is controlled by a surrounding heater. The vapour forms a molecular jet of defined geometry limited by an orifice. The vapour jet is condensed on a plate cooled down below - 100 °C by a surrounding copper baffle which is in contact with liquid nitrogen. The plate forms one end of an ultra micro balance.

The pressure of the test item is calculated from the weight increase during an elapsed time period.

The vapour pressure was at first measured in the temperature range of 21 °C to 31 °C by Effusion Method (Vapour Pressure Balance). The course of the vapour pressure show a broad scatter. From these data points it is concluded, that the measured vapour pressure is mainly influenced by volatile by-products, which are available in the test item only in limited quantities.

An additional measurement with the dynamic method was performed.

Vapour Pressure (Dynamic Method)

The vapour pressure is measured by determining the boiling point of the test item at various specified pressures between roughly 10 and 1000 hPa.

Before filling the test apparatus the whole equipment was flooded with nitrogen to minimize the presence of oxygen. After filling the apparatus with the test item the lowest desired pressure is set and the heating system is switched on. Equilibrium is reached when a constant boiling temperature is achieved at a given pressure. After recording this point the pressure is increased step by step and up to the boiling point.

The Antoine constants from the regression of all data from both methods (vapour pressure balance and dynamic method) were used to calculate the vapour pressure for 20, 25 and 50 °C, which were 0.17, 0.4 and 11 Pa respectively.

Key value for chemical safety assessment

Vapour pressure:

0.17 Pa

at the temperature of:

20 °C