Carbon monoxide with the maximum permissible concentration in the working area is 20 mg/m3 (MPCСО = 20 mg/m3), is a danger to the environment and humans. Although carbon monoxide is a strong reducing agent (θСО2 СО= -0,12 V), direct reaction with oxygen due to steric hindrance is either at high temperature, or in the presence of catalysts. According to the form of the active component, the catalysts can be oxide, metal and metal complex, and according to their temperature characteristics they are divided into low-temperature and high-temperature. The development of catalysts for low-temperature oxidation of CO for personal protective equipment of the respiratory system (RPE) is urgent. Respiratory catalysts must ensure stable air purification to a CO concentration lower than or equal to the MPCСО at ambient temperature and high humidity of the gasair mixture. Analysis of research in the field of development of catalysts for low-temperature oxidation of CO showed that Wacker-type metal-complex catalysts deposited on various carriers, containing palladium (II), copper (II) salts and other additives, are high potential. The natural mineral phogopite (N-Phl) was first used as a carrier for palladium – copper complexes that catalyze low-temperature oxidation of carbon monoxide by atmospheric oxygen. It was found that active catalytic compositions K2PdCl4-Cu(NO3)2-KBr/Х ̅ Н-Phl-1 are formed only on acid-modified phlogopite samples. Phlogopite was modified by the reflux method in a solution of nitric acid of various concentrations Х ̅ = 0.25; 0.5; 1.0; 3.0; 4.0; 6.0 and 8.0 mol/l for 1 hour. Samples (supports and catalysts) were characterized by XRD, SEM, FT-IR spectroscopy and pH metry. It was found that only at Х ̅ ≥ 3.0 mol l, the phlogopite samples undergo structural and morphological changes and the pH of the suspension decreases, which in total contributes to the achievement of such catalyst activity, which ensures stable air purification from CO to a concentration below the MPCСО = 20 mg/m3 for the working area.