“Nanocomposites and nanomaterials”

Catalyst containing natural nanosilica, palladium(II) and copper(II) salts in oxidation of carbon monoxide with oxygen 
Rakitskaya T.L., Nazar A.P., Kiose T.O.
Faculty of Chemistry and Pharmacy, Odesa I.I. Mechnikov National University,2, St. Dvoryanska, 65082, Odesa, Ukraine. 
E-mail: email.of. corresponding annnzr1401@gmail.com 

, mg/m3

Fig. Time dependence of the final concentration of CO during its oxidation in the presence of Pd(II)-Cu(II)/ catalyst
: 1 – 8H -Phl-1; 2 – 8H -Phl-24;
3 – 8H -Phl-48; 4 – 8 -Phl-72

τ, min

The search for readily available and cheap carriers for the basic components (K2PdCl4 and Cu(NO3)2) of a catalyst for low-temperature oxidation of carbon monoxide in the development of new functional nanomaterials is very important and actual. Phlogopite (Phl) concentrate is one of polyphase natural materials, which contains diopside, tremolite, and clinochlore phases in addition to the main phase. This work presents the results of the study of an influence of acid modification conditions on the phase and chemical composition of phlogopite concentrate. The samples were modified with 8M nitric acid at room temperature, the treatment time was 1; 24; 48; 72 hours. Samples 8H-Phl-1, 8H-Phl-24,   8H-Phl-48 and 8H-Phl-72 () were characterized by XRD, SEM, FT-IR spectroscopy, and pH-metry. The samples were used for the synthesis of catalysts with the composition Pd(II)-Cu(II)/. It is shown that in above row of indicated carriers the following trends are observed: the content of the Phl phase decreases, the content of the clinochlore phase increases, the content of diopside and tremolite phases changes irregularly; the content of silicon increases to 92 wt% of SiO2. The data of fig. demonstrate a decrease in the final concentration of CO in stationary mode with an increase in the duration of treatment of a carrier. In case of = 8H-Phl-72, the catalyst provides air purification from CO below MPC = 20 mg/m3.