In this paper, we examine the wet-air oxidation (WAO) of four nuclear-fuel-chelating compounds [diethylenetriaminepentaacetic acid (DTPA), ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), and thenoyltrifluoroacetone (TTA)]. The study focuses on the kinetics and mechanism of the degradation process. Identification of the free-radical intermediates was performed via the spin-trapping technique. The reaction of each compound studied was found to occur in two steps, with a partial order of one with respect to TOC for both steps. Among the compounds studied,TTA shows the most difficulty when degrading. Hydroxyl, hydroxycarbonyl, and nitrogenous radicals are some of those formed during the degradation process. Schematic reaction pathways, which can explain the formation of some mineral byproducts, are proposed an the basis of these radicals.