Carbonyl difluoride

Henry's Law constant

Administrative data

Endpoint:

Henry's law constant

Type of information:

other: Compilation of experimental measures

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

phototransformation in air

Remarks:

Tropospheric removal

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

GLP compliance:

not specified

DT50:

3.9 d

Remarks on result:

other: estimation of hydrolysis in the clouds using Henry's law constant = 20 M.atm-1 and unimolecular hydrolysis rate k(H)= 8 sec-1 from George et al., 1993.

Remarks:

'Heterogeneous removal process)

Conclusions:

The atmospheric lifetime of COF2 in cloud loss is reported to be 3.9 days. It is not expected to build up in the atmosphere.

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Reference

Endpoint:

phototransformation in air

Type of information:

experimental study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Principles of method if other than guideline:

- Principle of test: the tropospheric lifetime of halides was estimated from their dissolution potential in the aqueous phase
- Short description of test conditions: experimental phase was conducted at various pH and temperatures
- Parameters analysed / observed: determination of the Henry's law solubility (H) and hydrolysis rate (Khyd) and product H*khyd

GLP compliance:

not specified

Estimation method (if used):

PHOTOCHEMICAL REACTION WITH OH RADICALS: Not used, it is predicted to be negligible

DT50:

>= 5 - <= 10 d

Test condition:

Estimated minimum lifetime from tropospheric cloud processing. Determined at 278K.

Remarks on result:

other: Using Henry's constant of 1 M/atm. as maximum value

Reaction with:

other: cloud liquid water

Remarks on result:

other: khyd: > 5 and <500 sec-1

The tropospheric lifetime for COF2 was determined to be 0.5 - 3 days, using hydrolysis rate range 5 < k_hyd < 500 sec^-1 and at a temperature of 278K.

Whend considering cloud formation probabilities, the lower limit for the lifetime would be 5 -10 days.

Conclusions:

The tropospheric lifetime of Carbonyl fluoride derived from in cloud heterogeneous removal was estimated to be 5-10 days.

Data source

Reference

Reference Type:

review article or handbook

Title:

Compilation of Henry’s law constants (version 4.0) for water as solvent.

Author:

Sander R.

Year:

2015

Bibliographic source:

Atmos. Chem. Phys., 15:4399–4981 (www.atmos-chem-phys.net/15/4399/2015/)

Materials and methods

Principles of method if other than guideline:

Henry’s law constants of trace gases have been collected from existing publications and converted into a uniform format.

Test material

Test material information

Constituent 1

Reference substance name:

Carbonyl difluoride

EC Number:

206-534-2

EC Name:

Carbonyl difluoride

Cas Number:

353-50-4

Molecular formula:

CF2O

IUPAC Name:

carbonyl difluoride

Test material form:

gas

Results and discussion

Henry's Law constant H

Henry's Law constant H 1

H:

0.35 other: mol/m3.Pa (Henry's law solubility constant)

Remarks on result:

other: Mirabel et al. 1996

Remarks:

(Henry's law solubility constant)

Henry's Law constant H 2

H:

2.857 Pa m³/mol

Remarks on result:

other: Mirabel et al., 1996

Remarks:

(converted to Henry's law volatility constant using the conversion factor given in the publication)

Henry's Law constant H 3

H:

0.01 other: mol/m3.Pa (Henry's law solubility constant)

Temp.:

278 K

Remarks on result:

other: De Bruyn et al., 1995

Remarks:

(Henry's law solubility constant at 4.85°C); original value: H = 1 M/atm.

Henry's Law constant H 4

H:

101 Pa m³/mol

Temp.:

278 K

Remarks on result:

other: De Bruyn et al., 1995

Remarks:

(converted to Henry's law volatility constant using the conversion factor given in the publication)

Henry's Law constant H 5

H:

0.2 other: mol/m3.Pa (Henry's law solubility constant)

Temp.:

284 K

Remarks on result:

other: George et al., 1993

Remarks:

(Henry's law solubility constant at 10.85°C); original value cited in Kanakidou, 1995: H = 35 M/atm.

Henry's Law constant H 6

H:

5 Pa m³/mol

Temp.:

284 K

Remarks on result:

other: George et al., 1993

Remarks:

(converted to Henry's law volatility constant using the conversion factor given in the publication)