KINETICS OF HNO REACTIONS WITH O2 AND HNO

A perfected kinetic intracavity laser spectroscopy method based on a ring travelling wave dye laser with a highly linear algorithm for absorption spectra processing has been developed. Rate constants for the reactions (i) HNO+02-->k1 products, (ii) HNO+HNO-->k2 products have been measured over a temperature range 296-421 K using the developed method. Least-squares fits to Arrhenius expressions yield k1(T)=2.2 x 10(10) exp [-(4600+/-200)/T] cm3 mol-1 s-1, and k2(T)=3.7 x 10(11) x exp[-(1790+/-80)/T]cm3 mol-1 s-1. Heterogeneous HNO decay has been explored on a quartz surface. The fraction gamma of wall collisions that remove HNO obeys the relation 6.6 x 10(-4) exp[-(1530+/-90)/T] over a temperature range 296-421 K at initial concentrations [HNO]0 less than or similar 3.2 x 10(-12) mol/CM3.