Gas-phase rate constants for the reaction of NO3 radicals with furan and methyl-substituted furans

Rate coefficients have been determined for the gas-phase reaction of NO3 radicals with furan and methyl-substituted furans at T = 295 +/- 2 K in a flow system in the pressure range 6.8-200 mbar using N-2 as carrier gas. The rate constants obtained with the relative rate method are the following (in cm(3) molecule(-1) s(-1) units): furan, (9.98 +/- 0.62) x 10(-13); 2-methylfuran, (2.57 +/- 0.17) x 10(-11); 3-methylfuran, (2.86 +/- 0.06) x 10(-11); 2,5-dimethylfuran, (5.78 +/- 0.34) x 10(-11); 2,3-dimethylfuran, (5.83 +/- 0.46) x 10(-11); 2,4-dimethylfuran, (5.72 +/- 0.46) x 10(-11); tetramethylfuran, (1.184 +/- 0.16) x 10(-10). An assessment of the tropospheric lifetimes for furan and methyl-substituted furans with regard to NO3- and OH-attack shows that the NO3-initiated degradation of the considered species represents an important sink.