Abstract:
The samples of dispersed silica, tripoli from the Konoplyansky deposit, were used in this
work. Pd(II)–Cu(II) compounds fixed on dispersed silica for the oxidation of carbon
monoxide with air oxygen were obtained by impregnation of the carrier, which was
previously boiled in distilled water for one hour, through NH3-coordination in the presence
of ethyl alcohol, followed by maturation of the catalyst at 200C for 20 hours and drying at
3000C for 4 hours. The initial and chemically modified samples of tripoli were characterized
by X-ray phase analysis, IR-spectral and thermogravimetric research methods and tested
in the reaction of low-temperature oxidation of carbon monoxide with oxygen. The
degree of CO conversion in the stationary mode was used to estimate the activity of the
catalyst. It was established that the activity of copper-palladium catalysts is significantly
affected by the method of catalyst preparation, namely: the sequence of mixing the
starting solutions, the drying temperature, and the content of the catalyst components.
The catalyst with the highest activity contained all the components, such as K2PdCl4,
Cu(NO3)2, NH4OH, KBr, and Ñ2Í5ÎÍ, mixed beforehand in the specified sequence. It
provides air purification from CO to a concentration that is 5 times lower than the
maximum permissible concentration for the working area (MPCCO=20 mg/m3). The
degree of CO oxidation reaches 98.6%. With other variations of the method of the
catalyst preparation, the samples show much lower activity, which indicates the formation
of surface complexes of different composition, responsible for the oxidation of carbon
monoxide by air oxygen.
