HYDROXYL RADICAL-INDUCED DECOMPOSITION OF ALIPHATIC-ACIDS IN OXYGENATED AND DEOXYGENATED AQUEOUS-SOLUTIONS

The aim of this work was to study the oxidation of aliphatic acids by hydroxyl radicals resulting from the photolysis of hydrogen peroxide. Experiments carried out in dilute aqueous solutions (pH = 2.9-3.5) of mono and dicarboxylic acids with 1 to 4 carbon atoms showed (i) the ox idation of the carboxylic group is slow, (ii) the hydroxyl group of hy droxylated acids activates the adjacent C-H bond and leads, after hydr ogen atom abstraction, O-2 addition and HO2. removal, to the carbonyl group, (iii) a C-C bond cleavage occurs after hydrogen atom abstractio n and oxygen addition for unsubstituted dicarboxylic acids. Except for oxalic acid, the mechanism of oxidation into CO2 of the acids studied involves oxygen consumption and O-2(.-)/HO2. release.