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, [Al 13 O 4 (OH) 24 (H 2 O) 12 ] 7+ (Al 13), as an intercalating agent. The final product was used for preparing К 2 PdCl 4-Cu(NO 3) 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. К 2 PdCl 4-Cu(NO 3) 2-KBr/S compositions (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 Al 13 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 C Pd(II) = 2.72 × 10 −5 mol/g and copper(II) concentrations of 2.9 × 10 −5 and 5.9 × 10 −5 mol/g.

Progress and perspectives on pillared clays applied in energetic and environmental remediation processes

“…The acidity developed by PILCs is interesting for reactions as alkylation, dehydrogenation, hydrocracking and isomerization [25]. In the case of metal supported catalysts, the selective reduction of NOx [26,27], the complete oxidation of VOCs [28][29][30][31][32][33] and the wet hydrogen peroxide catalytic oxidation of wastewater [34,35] are the most interesting reactions where PILCs have been applied (see Figure 2).…”

Composition and Activity of Copper-Palladium Catalyst on Carbon Fiber Material for Air Purification from Carbon Monoxide

“…Another catalyst 1 containing 0.8 % PdCl 2 (converted to palladium), 10 % CuCl 2 and Al 2 O 3 carrier at C CO = 6250 mg/m 3 and t ef = 1.2 s and provides 100 % air purification from carbon monoxide. For the last 10-15 years our studies [9][10][11] were devoted to the kinetics of CO oxidation by oxygen in the presence of catalysts K 2 PdCl 4 -Cu(NO 3 ) 2 -KBr/ , where are the original and modified in various ways natural materials (clinoptilolite (Cl), mordenite (Mord), bentonite (Bent), trepel (Tr), basaltic tuff (BT)). Among the listed catalysts, only two catalysts based on acid-modified clinoptilolite and trepel are used in RPE.…”