Laboratory Measurements of the Hydroxyl Radical (OH)-Initiated Oxidation of Alpha and Beta-Pinene

Indiana University, Bloomington IN

Investigators

Abstract

This project consists of laboratory studies of the kinetics and mechanism of the reaction of OH (hydroxyl radical) with pinenes, which are important biogenic hydrocarbons. In the atmosphere, these reactions lead to the production of numerous products, including radicals, however, the details of the mechanism are not well understood. Relative rate measurements will be carried out in a small quartz chamber with direct sampling of the gas mixture and mass spectrometric detection as well as GC/MS (gas chromatography/mass spectrometry) analysis of compounds with low volatility. These studies can be carried out at various temperatures. Studies of the reactions of some of the reaction products (pinonaldehyde, nopinone) themselves with OH are also planned. Absolute measurements of the rate coefficients will be carried out using the turbulent flow technique. The results of this study will improve our knowledge of the details of the oxidation mechanisms and will be valuable in determining the efficiency of these biogenic hydrocarbons in the production of photochemical smog.