LOTASC: description and transnational access

1. Introduction

An aerosol simulation chamber has been removed from the Fraunhofer-Institute at Hannover and been reinstalled at the University of Bayreuth in the new refrigerator laboratory, coolable to -25°C to constitute a new facility the low-temperature aerosol simulation chamber (LOTASC). It mainly investigates the aerosol-partitioning of semi-volatile compounds and heterogeneous chemistry of adsorbents, as well as gas phase hydrocarbon reactivity at low temperature (down to -25°C). This will allow us to simulate tropospheric photochemistry, including cirrus clouds. LOTASC ispart of the Transnational Access of Euochamp-2.

2. Description of the research facility

Actually there are three smog chambers in the Atmospheric Chemistry Research Laboratory. One is the big glass chamber known as LOTASC; the second is a Teflon chamber which is located in the same refrigerator room with LOTASC and could achieve low temperature; the last chamber is a medium glass smog chamber connected with IR spectrum, and it could deliver aerosol experiment at room temperature. A variety of state-of-the-art analytical instrumentation including GC/FID/ECD, GC-MS, Ion Chromatography, HPLC-DAD-Fluorescent, and UV/VIS-Spectrometer is also available. For field measurement HONO Analyzer, NO2 and PAN Analyzer is available.

New instruments: A quadrupole MS (Pfeiffer Prisma Plus) has just arrived and is being tested with a temperature-programmed desorption/pyrolysis up to 1000°C. A Helium Ionization Detector, HID (VICI Model D-4-I) is being connected with a GC to determine aldehydes and other compounds with low FID response.

2.1. Technical data

The smog chamber is made of glass (Duran, Schott). The cooling of the chamber should decrease the evaporation of substance from the surface of the particles, and the experiments could be made at environmentally relevant temperature of the troposphere, for example at the middle, global tropospheric temperature or simulate even the Arctic climate. The size of the smog chamber limits the residence time of the agglomerates. This provides sufficient aerosol concentrations at longer durations of the experiment.

2.2. Images

2.3. Publications

Ofner, J; Krüger, HU; Zetzsch, C; Grothe, H: Direct Deposition of Aerosol Particles on an ATR Crystal for FTIR Spectroscopy Using an Electrostatic Precipitator, Aerosol Science and Technology, 43(8), 794-798 (2009)

Sen, A; Siekmann, F; Krüger, HU; Zetzsch, C: Investigation of atmospheric nanoparticles: Impact of sea salt and fate of organic molecules adsorbed on alumina, Phys. stat. sol., 243, 3546-3550 (2006)

Krüger, HU; Gavrilov, R; Liu, Q; Zetzsch, C: Entwicklung eines Persistenz-Messverfahrens für den troposphärischen Abbau von mittelflüchtigen Pflanzenschutzmitteln durch OH-Radikale; Schlussbericht zum Vorhaben UFOPLAN 201 67 424/02, (2005)

Palm, W; Elend, M; Krüger, U; Zetzsch, C: Atmospheric degradation of a semivolatile aerosol-borne pesticide: Reaction of OH with pyrifenox (an oxime-ether), adsorbed on SiO2, Chemosphere, 38, 1241-1252 (1999)

Behnke, Wolfgang; Nolting, Friedrich; Zetzsch, Cornelius. An aerosol smog chamber for testing abiotic degradation of compounds with low volatility. Pestic. Sci. Biotechnol., Proc. Int. Congr. Pestic. Chem., 6th (1987), Meeting Date 1986

For more publications, please click here.

2.4. Access to the chamber under Eurochamp TA

Access to LOTASC is provided through Eurochamp-2 Transnational Access and other collaborations. Please contact us find the appropriate setup for new projects at LOTASC.

LOTASC offers access to various types of instruments. There is another Teflon chamber whose temperature can also be lowered down to -25°C, recently it has been combined with a Differential Optical Absorbance Spectroscopy (DOAS) within the collaboration with the Institute of Environmental Physics of the University of Heidelberg, to detect trace gases, mainly absorbing light in the visible and ultraviolet wavelength range, such as OH, HONO, NO₃, OClO, BrO, IO, NO₂, NO, and NH₃ [Platt and Stutz 2008]. There is a third chamber-Medium size glass chamber combined with White cell and long path FTIR absorption (normally at room temperature) as on-line technique and FTIR with ATR and DRIFTS as offline techniques. It is possible to study aerosol formation and processing on a molecular level.

Modifications of inlet lines or flanges can be provided on request. Access to workshops and laboratories can be provided after consultation. Status data of the chamber and the data of the installed instruments are available for the user.

3. Institution in charge of the laboratory facility

The Atmospheric Chemistry Research Laboratory was founded in 2003. It is part of the Bayreuth Center of Ecology and Environmental Research (BayCEER) in the Geoecology Department of the University of Bayreuth.

The main areas of research and tasks are:
- Atmospheric photochemistry of volatile and semi-volatile organic compounds
- Heterogeneous chemistry on secondary organic aerosols and HULIS
- Photochemistry of sea salt aerosol and halogen activation
- Integration of Chambers for Investigating Atmospheric Processes within the Infrastructure EUROCHAMP-2

UBT is partner 4 in Eurochamp-2.

3.1. Contact Information

 Prof. Cornelius Zetzsch, phone: +49 921 55 5726, fax: +49 921 55 5729

 Prof. Andreas Held, phone: +49 921 55 5723, fax: +49 921 55 5729

Forschungsstelle für Atmosphärische Chemie
University of Bayreuth
Dr.-Hans-Frisch-Straße 1-3
95440 Bayreuth, Germany

4. Additional Information

As mentioned in 2.4 Access to the chamber under Eurochamp-2 TA, there are two more chambers in our institute. One is LOTASC Teflon Chamber, the other is a medium size glass chamber combined with FTIR absorption.

LOTASC Teflon Chamber

It is mainly designed for halogen activation experiment (also on soil). GC-FID and a new HID detector are connected with the chamber for trace gas detection. Recently, it has been combined with a Differential Optical Absorbance Spectroscopy (DOAS) within the collaboration with the Institute of Environmental Physics of the University of Heidelberg, to detect trace gases, mainly absorbing light in the visible and ultraviolet wavelength range, such as OH, HONO, NO₃, OClO, BrO, IO, NO₂, NO, NH₃ et al. [Platt and Stutz 2008]. For the smog chamber experiments in Bayreuth a Czerny/Turner-spectrograph with a photodiode array detector is used in combination with a multi-reflection cell (White[1942 & 1976]). Two sets of 3 mirrors each are required for the set-up of the multi-reflection cell.

Medium Size Glass Chamber

Medium size glass chamber combined with White cell and long path FTIR absorption (normally at room temperature) as on-line technique and FTIR with ATR and DRIFTS as offline techniques. It is possible to study aerosol formation and processing on a molecular level.