"Nanotechnology and nanomaterials"

Pd(II), Cu(II), and pillared clay based nanocatalysts for the low-temperature CO oxidation
Rakitskaya T.L.1, Dzhyga A.M.1, Kiose T.A.1, Oleksenko L.P.2, 
Volkova V.Y.1
1Department of Inorganic Chemistry and Chemical Ecology, Odessa I.I. Mechnikov Natuinal University. Dvoryanskaya St., 2, Odessa-65026, Ukraine.
E-mail: tlr@onu.edu.ua

2Department of Physical Chemistry, Kyiv Taras Shevchenko Natuinal University. Vladimirskaya St., 60, Kyiv-01601, Ukraine.

, mg/m3

, мг/м3

τ, min

N-Bent(D)

, мг/м3

Al-PILC

, мг/м3

Pillared clays are little-studied as supports in the compositions of metal-complex catalysts. In the work, pillared clay (Al-PILC) was prepared from Ukrainian bentonite (Dashukowskii deposit) and the aluminum polycation, [Al13O4(OH)24(H2O)12]7+ , differently,  Al13, was used as an intercalating agent.  The end product i.e. Al-PILC was impregnated with the Pd(II)-Cu(II) mixed solution for obtaining К2PdCl4-Cu(NO3)2-KBr/Al-PILC catalytic composition. Initial natural bentonite (N-Bent(D)), Al-PILC, and the catalytic composition were characterized by XRD, IR spectroscopy, thermogravimetric (DTG-DTA) analysis, water vapour adsorption, and pH-metry. The catalyst sample and also a sample of К2PdCl4-Cu(NO3)2-KBr/N-Bent(D) composition used for comparison, were tested in the reaction of CO oxidation with air oxygen at 20 ºC, a linear velocity of gas-air mixture (GAM) of 4.2 cm/s, a relative humidity of 67 % and an initial CO concentration in GAM of 300 mg/m3. The – τ profiles in Figure depicting the changes in CO concentration at the reactor outlet () with time (τ) were obtained for the above samples weighed 1 g each. It can be seen that the modification of natural bentonite by Al13 intercalation results in formation of the nanostructured catalyst with a crystallite size of 19 nm providing CO oxidation in the steady-state mode.