KINETICS AND NITRO-PRODUCTS OF THE GAS-PHASE OH AND NO3 RADICAL-INITIATED REACTIONS OF NAPHTHALENE-D8, FLUORANTHENE-D10, AND PYRENE

The kinetics and nitroarene product yields of the gas‐phase reactions of naphthalene‐d8, fluoranthene‐d10, and pyrene with OH radicals in the presence of NOx and in N2O5NO3NO2air mixtures have been investigated at 296 ± 2 K and atmospheric pressure of air. Using a relative rate method, naphthalene‐d8 was shown to react in N2O5NO3NO2air mixtures a factor of 1.22 ± 0.10 times faster than did naphthalene, with the 1‐ and 2‐nitronaphthalene‐d7 product yields being similar to those of 1‐ and 2‐nitronaphthalene from naphthalene. From the measured PAH concentrations and the nitroarene product yields, formation yields of 2‐, 7‐, and 8‐nitrofluoranthene‐d9 and 2‐ and 4‐nitropyrene of 0.03, 0.01, 0.003, 0.005, and 0.0006, respectively, were determined from the OH radical‐initiated reactions. Effective rate constants for the reactions of fluoranthene‐d10 and pyrene with N2O5 in N2O5;NO3NO2air mixtures of ca. 1.8 × 10−17 cm3 molecule−1 s−1 and ca. 5.6 × 10−17 cm3 molecule−1 s−1, respectively, were derived. Formation yields of 2‐nitrofluoranthene‐d9 and 4‐nitropyrene of ca. 0.24 and ca. 0.0006, respectively, were estimated for these reaction systems. 2‐Nitropyrene was also observed to be formed in these N2O5NO3NO2 reactions, but was found to be a function of the NO2 concentration and, therefore, would be a negligible product under ambient NO2 concentrations. These product and kinetic data are consistent with ambient air measurements of the nitroarene concentrations. Copyright © 1990 John Wiley & Sons, Inc.