1 Effect of the Chemical Composition of Mesoporous 2 Cerium - Zirconium Oxides on the Modification with 3 Sulfur and Gold Species and Their Application in 4 Glycerol Oxidation 5
نویسنده
چکیده
Ceria, zirconia and mixed cerium-zirconium mesoporous oxides were synthesized and 12 used as supports for sulfur and gold species. The materials were characterised using selected 13 advanced techniques (ICP-OES, elemental analysis, XPS, XRD, N2 adsorption and desorption 14 isotherms, UV-vis, ATR-FTIR, TPR-H2, TG-DTA) which allowed monitoring of the oxidation state 15 of metals (cerium and gold) and the surface properties of the catalysts, in particular the 16 concentration of the components on the surface and in the bulk of materials. The interactions 17 between gold, sulfur and metals from oxides were considered. The goal of this work was studied 18 the changes in the chemical composition of materials and the oxidation states of cerium species 19 after the modification of oxides with sulfur and gold species and the estimation of the influence of 20 these changes on the surface properties. The chemical composition of surface affects the mobility of 21 surface oxygen and the oxidation state of cerium, which can play the role of redox sites (e.g. 22 Ce3+/Ce4+ species), and therefore it strongly influences on the adsorption of hydrogen sulfide and 23 then gold loading. Additionally, gold catalysts modified with sulfur species were tested in the 24 reaction of glycerol oxidation in the liquid phase at basic conditions as the test reaction of the 25 catalytic oxidation of organic pollutants from water. 26
منابع مشابه
1 Effect of Selected Factors on Catalytic Activity of 2 Bimetallic Copper - Gold Catalysts in Selective 3 Oxidation of Glycerol 4
A current problem in petrochemical industry is the elimination of crude glycerol which is 11 the by-product of biodiesel production obtained during the transesterification of vegetable oils and 12 animal fats. In this work are presented the results of characterisation of mesoporous ceria, zirconia 13 and mixed cerium-zirconium oxide modified with gold and/or copper species and their application...
متن کاملSynthesis of thermally stable mesoporous cerium oxide with nanocrystalline frameworks using mesoporous silica templates.
Highly ordered mesoporous cerium oxides, composed of nanocrystalline pore walls and exhibiting high thermal stability even at 973 K, were synthesized using mesoporous silica templates with hexagonal p6mm and cubic Ia3d symmetries.
متن کاملActivity of Cu-Co-M (M= Ce, Ni, Au, Mg) catalysts prepared by coprecipitation method, calcined at high temperature for CO oxidation
The present study deals with analysis of the activity of catalysts prepared by addition of different metals to Copper and Cobalt based catalysts for CO oxidation and the variation in activity caused by changes in composition. A series of catalysts were prepared with Cu:Co molar ratio 1:4 and a third metal (M= Ce, Ni, Au, Mg) was added in three different quantities. Compositions were prepared by...
متن کاملMesoporous Silica Based Gold Catalysts: Novel Synthesis and Application in Catalytic Oxidation of CO and Volatile Organic Compounds (VOCs)
Gold nanoparticles, particularly with the particle size of 2–5 nm, have attracted increasing research attention during the past decades due to their surprisingly high activity in CO and volatile organic compounds (VOCs) oxidation at low temperatures. In particular, CO oxidation below room temperature has been extensively studied on gold nanoparticles supported on several oxides (TiO2, Fe2O3, Ce...
متن کاملActivity of Cu-Co-M (M= Ce, Ni, Au, Mg) catalysts prepared by coprecipitation method, calcined at high temperature for CO oxidation
The present study deals with analysis of the activity of catalysts prepared by addition of different metals to Copper and Cobalt based catalysts for CO oxidation and the variation in activity caused by changes in composition. A series of catalysts were prepared with Cu:Co molar ratio 1:4 and a third metal (M= Ce, Ni, Au, Mg) was added in three different quantities. Compositions were prepared by...
متن کامل