UCPH: description and transnational access

1. Introduction

Two facilities are available at the Department of Chemistry, University of Copenhagen:

  1. The Photochemical Reactor: a custom built simulation chamber for investigating the kinetics and spectroscopy of systems of atmospheric interest. Design features include UV-A, UV-C and sun lamps, a quartz reaction cell, temperature control and a vacuum FTIR spectrometer. We have used this system in relative rate studies to investigate CFC replacements, greenhouse gases and biofuel compounds.
  2. The Smog Chamber: a custom built simulation chamber for investigating the formation, growth and properties of atmospheric particles. The system is equipped with instruments for measurement of particle size and number concentration, evaporation rates and cloud nucleating abilities.

2. Description of the research facility

The Photochemical Reactor is made of a 2 m quartz tube with electropolished staineless steel end flanges on which are mounted gold-coated multipass mirrors in a White geometry. Absorption path lengths of up to 184 m have been achieved but the system is typically operated at 80 m. The cell is surrounded by three lamp systems, currently UV-A, UV-C and sun-lamps. We have also done experiments with UV-B and sodium lamps. The reaction chamber and lamps sit inside an insulated box. The temperature of the system is controlled by a compressor/heat exchanger/fan system that circulates regulated air around the reaction vessel. The range of temperatures is 240 to 350 K. Spectra are recorded using a Bruker 66 Fourier Transform interferometer with a resolution of 0.125 1/cm. A number of detectors and filters are available. The entire optical path is under vacuum to minimize interference by CO2 and H2O absorptions. A control program scans the interferometer and turns on and off the lamps. Reaction rates are determined using the relative rate method. Reaction products and absorption cross sections are also determined. One of the advantages of the Copenhagen photochemical reactor is that ozone can be photolysed directly to produce O1D since the quartz cylinder is transparent to 200 nm. This results in higher OH concentrations than can be achieved in similar systems using Pyrex glass.
The Smog Chamber consists of a Teflon bag (DuPont 125 mm) suspended from a metal frame in a temperature controlled laboratory. The dimensions of the chamber are 2.65 x 3.15 x 2.95 giving a total volume of ~25 m3. It is equipped with atomizers for generation of seed particles, Scanning Mobility Particle Sizers for measurement of particle size distributions and two cloud condensation nucleus counters (a static thermal diffusion type chamber build at the University of Wyoming as well as a continuous flow chamber from Droplet Measurement Technologies). A modified TDMA system including a 3.5 m long laminar flow reactor [7,8] allows for measurement of evaporation rates of aerosol particles at ambient conditions of temperature and relative humidity.

2.1. Technical data

2.2. Images

2.3. Publications

  1. Andersen, M.R.S., et al., Atmospheric chemistry of trans-CF3CH = CHCl: Kinetics of the gas-phase reactions with Cl atoms, OH radicals, and O-3. Journal of Photochemistry and Photobiology a-Chemistry, 2008. 199(1): p. 92-97.
  2. Andersen, V.F., et al., Methyl acetate reaction with OH and Cl: Reaction rates and products for a biodiesel analogue. Chemical Physics Letters, 2009. 472(1-3): p. 23-29.
  3. Nilsson, E.J.K., C. Eskebjerg, and M.S. Johnson, A photochemical reactor for studies of atmospheric chemistry. Atmospheric Environment, 2009. 43(18): p. 3029-3033.
  4. Nilsson, E.J.K., M.S. Johnson, and C.J. Nielsen, Isotope Effects in the Reactions of Chloroform Isotopologues with Cl, OH, and OD. Journal of Physical Chemistry A, 2009. 113(9): p. 1731-1739.
  5. Nilsson, E.J.K., et al., Kinetics of the Gas-Phase Reactions of Chlorine Atoms With CH2F2, CH3CCl3, and CF3CFH2 over the Temperature Range 253-553 K. International Journal of Chemical Kinetics, 2009. 41(6): p. 401-406.
  6. Nilsson, E.J.K., et al., Atmospheric chemistry of cis-CF3CH=CHF: Kinetics of reactions with OH radicals and O-3 and products of OH radical initiated oxidation. Chemical Physics Letters, 2009. 473(4-6): p. 233-237.

2.4. Access to the chamber under Eurochamp TA

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3. Institution in charge of the laboratory facility

The Department of Chemistry is the largest chemical research institution in Denmark. The Department is part of the University of Copenhagen, one of the oldest Universities in Northern Europe and the leading University in Scandinavia. In addition to research the department is responsible for teaching students in chemistry, biochemistry, molecular biomedicine and nanotechnology.

UCPH is partner 13 in Eurochamp-2.

3.1. Contact Information

 Matthew S. Johnson

 Merete Bilde

 Ole John Nielsen

Department of Chemistry
University of Copenhagen
Universitetsparken 5
DK-2100 Copenhagen Denmark

4. Additional Information

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