Experimental Study of the Reaction of Isopropyl Nitrate with OH Radicals: Kinetics and Products

The kinetics of the reaction of isopropyl nitrate (IPN) with OH radicals has been studied using a low-pressure flow tube reactor coupled with a quadrupole mass spectrometer: OH + (CH3)(2)CHONO2 products (2). The rate constant of the title reaction was determined using both the absolute method, monitoring the kinetics of OH radicals consumption in excess of IPN, and the relative rate method using the reaction of OH with Br-2 as reference one and following HOBr formation. As a result of the absolute and relative measurements, the overall rate coefficients, k(2) = (6.6 +/- 1.2) x 10(-13) exp(-(233 +/- 56)/T) was determined at a pressure of 1 Torr of helium over the temperature range 268-355 K. Acetone, resulting from H-atom abstraction from the tertiary C-H bond of IPN followed by 2-nitroxy-2-propyl radical decomposition, was found to be a major reaction product with the yield of 0.82 +/- 0.13, independent of temperature in the range 277-355 K.