CRAC1: description and transnational access

1. Introduction

CRAC1 is a custom-built simulation chamber designed for laboratory-based investigations of atmospheric processes such as the oxidation of volatile organic compounds and secondary organic aerosol formation. CRAC1 is part of the Transnational Access of Euochamp-2.

2. Description of the research facility

CRAC1 is a 3.91 m³ (3,910 L) cylinder made of fluorine-ethene-propene (FEP) foil surrounded by UV-visible lamps. The chamber is operated using purified dry air at atmospheric pressure and ambient temperature. Water can be added to the chamber to vary the relative humidity. Between experiments the chamber is flushed with clean air. The chamber is equipped with a wide range of instrumentation for chemical analysis, including GC and GC-MS (Varian Saturn 2000) for the detection of organic reactants and products, automated analyzers for monitoring nitrogen oxides and ozone, and in situ FTIR spectroscopy (path length 230 m). A scanning mobility particle sizer (SMPS) consisting of a condensation particle counter (TSI 3022A) and an electrostatic classifier (TSI 3071A) is used to measure the number concentration and size distribution of aerosol particles.

The main areas of research supported by the UCC chamber are studies of the atmospheric oxidation of volatile organic compounds (VOCs) to determine rate coefficients, reaction products and secondary organic aerosol formation. One of the unique techniques currently available is a novel denuder-filter system coupled with GC-MS analysis for the simultaneous measurement of gas and particle phase VOC oxidation products. In EUROCHAMP 2 the UCC chamber will be equipped with two new analytical tools; an aerosol time-of-flight mass spectrometer (ATOFMS) for the on-line analysis of secondary organic aerosol and a custom-built cavity enhanced absorption spectroscopy (CEAS) system for the detection of nitrate radicals. Both techniques will be unique within the EUROCHAMP consortium and will therefore enable UCC to provide unique research opportunities in the areas of secondary organic aerosol and nitrate radical reactions respectively.

2.1. Technical data

2.2. Images

2.3. Publications

Kourtchev, I., Bejan, I., Sodeau, J. R., and Wenger, J. C. Gas-phase reaction of (E) - ß-farnesene with ozone: Rate coefficient and carbonyl products, Atmospheric Environment, 43, 3182-3190, 2009.

Cécile Coeur-Tourneur, Alexandre Tomas, Angélique Guilloteau, Françoise Henry, Frédéric Ledoux, Nicolas Visez, Véronique Riffault, John C. Wenger, Yuri Bedjanian Aerosol formation yields from the reaction of catechol with ozone Atmospheric Environment, 43, 2360-2365, 2009.

R.M. Healy, B. Temime, K. Kuprovskyte and J.C. Wenger Effect of Relative Humidity on Gas/Particle Partitioning and Aerosol Mass Yield in the Photooxidation of p-Xylene Environmental Science & Technology, 2009, 43, 1884-1889.

R.M. Healy, J.C. Wenger, A. Metzger, J. Duplissy, M. Kalberer and J. Dommen Gas/particle partitioning of carbonyls in the photooxidation of isoprene and 1,3,5-trimethylbenzene Atmospheric Chemistry and Physics, 2008, 8, 3215-3230.

Max R. McGillen, Trevor J. Carey, Alex T. Archibald, John C. Wenger, Dudley E. Shallcross and Carl J. Percival Structure-activity relationship (SAR) for the gas-phase ozonolysis of aliphatic alkenes and dialkenes Physical Chemistry Chemical Physics, 2008, 10, 1757-1768.

B. Temime, R.M. Healy and J.C. Wenger A Denuder-Filter Sampling Technique for the Detection of Gas and Particle Phase Carbonyl Compounds Environmental Science & Technology, 2007, 41, 6514-6520.

N. Carrasco, J-F. Doussin, M. P. O'Connor, J.C. Wenger, B. Picquet-Varrault, R. Durand-Jolibois and P. Carlier Simulation Chamber Studies of the Atmospheric Oxidation of 2-Methyl-3-Buten-2-ol: Reaction with Hydroxyl Radicals and Ozone under a Variety of Conditions Journal of Atmospheric Chemistry, 2007, 56, 33-55.

D.S. Venables, T. Gherman, J. Orphal, J.C. Wenger and A.A. Ruth High Sensitivity in situ Monitoring of NO3 in an Atmospheric Simulation Chamber using Incoherent Broadband Cavity-Enhanced Absorption Spectroscopy Environmental Science & Technology, 2006, 40, 6758-6763.

G.M. Clifford and J.C. Wenger Rate coefficients for the gas-phase reaction of hydroxyl radicals with the dimethylbenzaldehydes International Journal of Chemical Kinetics, 2006, 38, 563-569.

G.M. Clifford, L.P. Thüner, J.C. Wenger and D.E. Shallcross Kinetics of the Gas-Phase Reactions of OH and NO3 Radicals with Aromatic Aldehydes Journal of Photochemistry and Photobiology A: Chemistry, 2005, 176, 172-183.

L.P. Thüner, P. Bardini, G.J. Rea and J.C. Wenger Kinetics of the Gas-Phase Reactions of OH and NO3 Radicals with Dimethylphenols Journal of Physical Chemistry, A, 2004, 108, 11019-11025.

2.4. Access to the chamber under Eurochamp TA

Visits will be typically 10-15 working days duration and organised at least 1 month in advance with the permanent scientists at UCC (John Wenger and Dean Venables). All equipment will be available to the users. The work will be treated as a collaborative research effort and joint authorship of any resulting papers or conference proceedings is expected. The users will work closely with the permanent scientists and the postdoctoral researchers and PhD students who regularly use the facility. All necessary training and guidance will be provided, from experimental design and procedures to data analysis. Requests for access to the CRAC1 chamber are processed centrally within EUROCHAMP 2.

3. Institution in charge of the laboratory facility

University College Cork (UCC) was founded in 1845 and today has over 14,500 students and 1,800 staff. It is the largest Irish university outside the capital, Dublin and has the highest research income of all the higher level institutions in the state. Research in environmental sciences is a high strategic importance in UCC and is facilitated by the recently established Environmental Research Institute (ERI).

UCC is partner 5 in Eurochamp-2.

3.1. Contact Information

 Dr John Wenger, phone: +353 21 4902454

 Dr Dean Venables, phone: +353 21 4902439

4. Additional Information

The research team at UCC currently offer excellent facilities and a stimulating research environment for visiting researchers. During 2005-2010 UCC hosted on average 4 visiting researchers per year from France, Spain and UK. This collaborative work has resulted in several research papers in the areas of kinetic and mechanistic studies of VOC oxidation (University of Paris, Universities of Manchester and Bristol) and the development of new methods for determining the composition of secondary organic aerosol (University of York).

http://crac.ucc.ie
http://www.ucc.ie
http://eri.ucc.ie