Rate constants for the reactions of NO3•, SO4•− and Cl• radicals with formate and acetate esters in aqueous solution

Abstract

Rate constants for the reactions of NO₃^•, SO₄^•− and Cl^• with the esters methyl formate, ethyl formate, methyl acetate and ethyl acetate in aqueous solution have been measured using pulse radiolysis and laser flash photolysis. The reactivities of NO₃^•, SO₄^•− and Cl^• are compared with ^•OH and found to be roughly in the order Cl^•≈^•OHNO₃^•≈SO₄^•−. The rates of reaction of NO₃^• with the formate esters in the aqueous phase are about four orders of magnitude faster than their corresponding gas phase reactions. In contrast, the rate constants for reaction of Cl^• with formate and acetate esters in the aqueous phase are about 100 times smaller than the gas phase values.