KINETICS AND MECHANISM FOR THE REACTIONS OF HALOGENATED ORGANIC COMPOUNDS IN THE TROPOSPHERE

Objective

The objectives are to identify uncertainties regarding the potential environmental effects of the proposed substitutes of the current used CFCs, eg, hydrochlorofluorocarbons and hydrofluorocarbons.
The data obtained in this project have greatly contributed to demonstrate that the secondary degradation products of the halocarbons, especially the HCFCs, have a negligible effect on stratospheric ozone. The rate constant data provided for the primary reaction with OH have been used to determine the lifetimes of the halocarbons, which are key parameters in the calculation of the ozone depletion potential and greenhouse warming potential for these compounds.
The project is concerned with the kinetics and mechanisms of oxidation of chlorine and bromine containing compounds under atmospheric conditions. For an accurate assessment of the ozone depletion potential the degradative oxidation mechanisms of several alternative CFCs products will be investigated, with particular emphasis on the determination of tropospheric sinks for their degradation intermediates.

The rate constants will be determined for a number of these intermediates.

The following processes will be investigated:

reactions of hydroxylradicals with halogenated alkanes and aldehydes;
absorption cross sections and photolysis for halogenated carbonyl compounds;
mechanisms for the oxidation of halogenated alkanes.

Fields of science

• natural sciences › chemical sciences › electrochemistry › electrolysis
• natural sciences › earth and related environmental sciences › environmental sciences › ozone depletion
• natural sciences › chemical sciences › inorganic chemistry › halogens
• natural sciences › earth and related environmental sciences › atmospheric sciences › meteorology › troposphere
• natural sciences › chemical sciences › organic chemistry › organohalogen compounds

Programme(s)

• FP2-STEP - Two specific research and technological development programmes (EEC) in the field of the environment STEP/EPOCH - STEP -, 1989-1992

Topic(s)

Data not available

Call for proposal

Data not available

Funding Scheme

CSC - Cost-sharing contracts

Coordinator

UNIVERSITY COLLEGE DUBLIN

Address

Belfield
4 Dublin
Ireland

Links

Participants (8)

BERGISCHE UNIVERSITAET GESAMTHOCHSCHULE WUPPERTAL

Germany

Address

Gauss Strasse 20
42097 Wuppertal

Links

Centre National de la Recherche Scientifique (CNRS)

France

Address

351 Cours De La Libération
33405 Talence

MAX-PLANCK-GESELLSCHAFT ZUR FOERDERUNG DER WISSENSCHAFTEN E.V.

Germany

Address

Johann Joachim-becher-weg 27
55020 Mainz

RISOE NATIONAL LABORATORY

Denmark

Address

Frederiksborgvej 399
Roskilde

THE CHANCELLOR, MASTERS AND SCHOLARS OF THE UNIVERSITY OF OXFORD

United Kingdom

Address

University Offices, Wellington Square
Oxford

Links

UNIVERSITAET HANNOVER

Germany

Address

Welfengarten 1 B
30167 Hannover

UNIVERSITE DE BORDEAUX I

France

Address

Cours De La Libération 351
33405 Talence

United Kingdom Atomic Energy Authority

United Kingdom

Address

353,harwell
OX11 0RA Didcot - Oxfordshire