In GVL, a promising second generation biofuel component, only ring opening reactions are important, acetic acid and CO2 being the only observed volatile products. However, the products of the reactions are found to be different. The tropospheric life times of GVL and AMGBL based on their reaction with OH under ambient conditions are comparable, 71.2 and 76.7 h respectively. Values of the rate coefficients of the reactions of GVL (kOH = (1.95 ± 0.58) x 10⁻¹² kCl = 2.26 ± 0.53 × 10⁻¹¹ cm³molecule⁻¹s⁻¹) and AMGBL (kOH = 1.81 ± 0.43 × 10⁻¹² kCl = 3.42 ± 0.63 × 10⁻¹¹ cm³molecule⁻¹s⁻¹) at 298 K imply that reaction with OH is the dominant reaction in the ambient conditions, and that reaction with Cl atom becomes relevant under marine boundary layer (MBL) conditions, reducing the tropospheric lifetimes to almost half. Tropospheric lifetimes of two lactones, gamma-valerolactone (GVL) and alpha-methyl gamma-butyrolactone (AMGBL) in terms of their reactions with two important tropospheric oxidants- OH and Cl - are estimated, after determining the respective rate coefficients of their reactions in the gas phase using relative rate method.
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