Pd(II), Cu(II), and pillared clay based nanocatalysts for low-temperature CO oxidation

Abstract

Pillared clays (PILCs) are little-studied as supports in compositions of anchored metal complex catalysts. In the work, pillared clay, Al-PILC, was prepared by using Ukrainian natural bentonite, N-Bent, and the aluminum polycation, [Al13O4(OH)24(H2O)12]7+ (Al13), as an intercalating agent. The final product was used for preparing К2PdCl4–Cu(NO3)2–KBr/Al-PILC nanocatalysts by an impregnation method. Initial N-Bent and Al-PILC as well as the nanocompositions based on them were characterized by XRD, FT-IR spectroscopy, DTG–DTA, water vapor adsorption, and pH metry. К2PdCl4–Cu(NO3)2–KBr/ $${\bar{\text{S}}}$$ compositions ( $${\bar{\text{S}}}$$ were N-Bent or Al-PILC) were tested in the reaction of CO oxidation with air oxygen at temperature of 20 °C and a relative humidity of 67%. It has been found that the preliminary modification of natural bentonite by Al13 intercalation results in formation of the nanostructured catalyst with a crystallite size of 19 nm showing the maximum activity in the reaction under study at CPd(II) = 2.72 × 10−5 mol/g and copper(II) concentrations of 2.9 × 10−5 and 5.9 × 10−5 mol/g.