Abstract (PDF) Graphical Abstract: The effect of halide ions (X= Cl−, Br−, I−) on the kinetics of ozone decomposition by compositions supported on the natural bentonite of the Dashukovske deposit in Ukraine (N-Bent(D)) has been studied. The obtained results have shown that the activity of the KX/N-Bent(D) composition in the ozone decomposition reaction increases in the row KCl << KBr < KI, which correlates with an increase in their reducing properties (the redox potential of the Х2/2Х− pair decreases). Such catalyst compositions can be recommended for applying in personal protective equipment for the respiratory system.