Essential oil of Platycladus orientalis (L.) Franco obtained from branches and leaves by steam distillation followed by vacuum distillation

Boiling point

Link to relevant study record(s)

Reference

Endpoint:

boiling point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

11 October and 12 October 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

The study was conducted according to an internationally recognised method, and under GLP. The test substance is adequately characterised. Therefore full validation applies.

Qualifier:

according to guideline

Guideline:

OECD Guideline 103 (Boiling Point)

Version / remarks:

1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.2 (Boiling Temperature)

Version / remarks:

2008

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

Inspected on 4,5 and 6 July 2016/ Signed on 10 January 2017

Type of method:

differential scanning calorimetry

Key result

Boiling pt.:

183 °C

Atm. press.:

101.3 kPa

Results

All the raw data (calibration, pre-test and main tests) is in the experimental report.

Pre-study

An endothermic peak assigned to the boiling of the substance was observed and measurement was stopped at 260°C. The initial boiling point of the substance was observed at 185.0°C. Temperature corresponding to this peak was used to create the following temperature program:

Step	Initial temperature (°C)	Final Temperature (°C)	Heating rate (°C/min)	Duration (min)	Furnace atmosphere	Rate* (mL/min)	Liquid nitrogen cooling
1	20	260	10	24	N2	40	NO

*Gas injection rate in the furnace.

 

Test 1:

Mass taken: 10.51 mg

The initial boiling point was observed at 181.5°C (onset temperature of peak) and a corresponding mass loss was observed on the TG curve, showing that all the substance was evaporated at the end of the study.

The crucible was visually checked after the determination: By opening the crucible, no test item left in the crucible and no sign of decomposition was observed.

Atmospheric pressure: 97.5 kPa.

Test 2:

Mass taken: 12.02 mg

The initial boiling point was observed at 181.7°C (onset temperature of the peak) and a corresponding mass loss was observed on the TG curve, showing that all the substance was evaporated at the end of the study.

The crucible was visually checked after the determination: By opening the crucible, no test item left in the crucible and no sign of decomposition was observed.

Atmospheric pressure: 98.2 kPa.

Conclusion

The initial boiling point of the test item was determined to be 181.5°C at 97.5 kPa for the first determination and 181.7°C at 98.2 kPa for the second determination.

In case of small pressure deviations the boiling temperature at standard pressure can be calculated following the equation of Sidney-Young:

T_n= T + (ƒ x ∆p)

T_n= boiling point at 101.325 kPa in K

T = measured boiling point in K

ƒ  = correctionfactor (tabulated value)

∆p= (101.325 – p) kPa

P= measured atmospheric pressure in kPa

The corrected values following Sidney-Young equation were determined to be 183.0°C (mean of 183.0°C at 101.3 kPa for the first determination and 182.9°C at 101.3 kPa for the second determination).

Apparatus Check

-Temperature

Reference substance: Indium

Expected melting point: 156.6 +/- 0.5°C

Obtained melting point: 156.1°C

The melting point of the Indium respects the defined tolerance of the expected melting point.

-Sensitivity

Reference substance: Indium

Expected enthalpy: 28.6 +/- 2.9 J/g

Obtained enthalpy: 28.57 J/g

The enthalpy of the indium respects the defined tolerance of the expected enthalpy.

Conclusions:

The corrected values following Sidney-Young equation were determined to be 183.0°C.

Executive summary:

The study was performed in order to determine the boiling point of test item according to OECD 103, resp. EU A.2, using the DSC method.

Two trials were conducted and corresponding thermograms were obtained (181.5°C at 97.5 kPa and 181.7°C at 98.2 kPa). The initial boiling point values respect validity criteria (less than 0.5°C of difference up to 326.85°C).

Moreover, the melting point of the Indium respects the checking cards limits (156.1°C for a reference value of 156.6°C) so as its enthalpy (28.57 J/g for a reference value of 28.6 J/g). After correction using the Sydney Young equation, the initial boiling point of the substance was determined as 183.0 °C at 101.3 kPa (mean of 183.0 °C for the first determination and 182.9 °C for the second determination).

Description of key information

The initial boiling point of the substance was determined as 183.0 °C at 101.3 kPa (mean of 183.0 °C for the first determination and 182.9 °C for the second determination).

Key value for chemical safety assessment

Boiling point at 101 325 Pa:

183 °C

Additional information

A fully reliable experimental study, conducted according to OECD 102/ EU A1 guideline is available.

It is considered as a key study.