Homogeneous nucleation of sulfuric acid and water mixture: experimental setup and first results
1Laboratory of Aerosol Chemistry and Physics, Institute of Chemical Process Fundamentals Academy of Sciences of the Czech Republic, Rozvojová 135, 165 02 Prague 6, Czech Republic
2Finnish Meteorological Institute, Erik Palménin aukio 1, P.O. Box 503, 00100 Helsinki, Finland
3Department of Physical Sciences, University of Helsinki, P.O. Box 64, 00014 Helsinki, Finland
Abstract. In this study we introduce a new flow tube suitable for binary and ternary homogeneous nucleation studies. The production of sulfuric acid and water vapor mixture, the experimental setup and the method of sulfuric acid concentration determination are discussed in detail. Wall losses were estimated from the measured sulfuric acid concentration profiles along the flow tube and compared to a theoretical prediction. In this investigation the experimental evidence of new particle formation was observed at a concentration of 109 molecules cm−3 of sulfuric acid and the nucleation rates measured at three relative humidities (RH) 10, 30 and 50%, cover six orders of magnitude, from 10−3 to 103 particles cm−3. Particle free air was used as a carrier gas. Our initial results are compared to the theoretical prediction of binary homogeneous nucleation, to results obtained by other investigators, and to atmospheric nucleation.