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Supported binary indium–cobalt oxide catalysts showed high activity in joint reduction of nitrogen(I, II) oxides with carbon monoxide. Their activity is determined not only by the composition, but also by the order of introducing the active components. In moist reaction systems (N2O + NO + CO + H2O), the best results were reached on In2O3,Co3O4/Al2O3 catalysts: 90–98% conversion of the reactants at 450–500˚C.

Hierarchical alumosilicate BEA zeolites with aggregated nanoparticle morphology and MOR zeolites with nanolayer morphology possess high concentrations of Bronsted and Lewis acid sites localized on the rather well-developed mesopore surface. The hydrogen forms of the starting BEA and MOR zeolites as well as their analogs modified by indium oxide display catalytic activity in the combined reduction of N 2 O and NO by propylene.

Among the studied (Pd), Co-, Ce-, Zr-oxide catalysts including catalysts deposited on structured cordierite support, the catalyst prepared by co-deposition of ceria and cobalt oxide is characterized by higher activity in reaction of reduction of nitrogen(I), (II) oxides (CO + NO, N2O + NO + CO) compared with samples prepared by successive deposition. This may be caused by an increase in both mobility of surface oxygen and dispersity of components in the catalytic composition.

Co- and Ag-containing catalysts on structured supports were investigated for use in DeNO x processes, in particular, in the process of combined reduction of N 2 O and NO with carbon monoxide and in selective catalytic reduction of NO with C 2 and C 4 alcohols. It was shown that doping of cobalt–cerium–zirconium oxide with 0.1 wt.% of Pd significantly lowers the temperature for achieving high conversions of N 2 O and NO (up to 200–300 °C) in a reaction mixture containing N 2 O, NO, CO and O 2 . The activity of Ag/Al 2 O 3 /cordierite catalysts in the selective reduction of nitrogen oxides by ethanol and butanol rises with increasing of Al 2 O 3 loading and depends on the optimal silver content added. Silver is associated with the regulation of redox and acid–base properties of the catalyst surface.

It is shown that palladium–cobalt oxide–cerium catalyst deposited on cordierite catalyzes the reduction of nitrogen(II) oxide with carbon monoxide, and cobalt–iron catalysts in simultaneous reduction of NO + N2O with C3-C4 alkanes retained high activity in the presence of water vapor and sulfur dioxide. The Pd-Co3O4/cordierite catalyst exceeds the Pt-Co3O4/codierite catalyst in the conversion of NO and CO in the reaction mixture CO + NO + O2 + H2O + SO2. Modification of the Pd-Co3O4/cordierite with cerium oxide considerably increases its sulfur resistance.

The combined conversion conditions were examined for the reactions of decomposition and reduction of N2O and NO with C1,C3–C4 hydrocarbons, in particular, in gas mixtures containing oxygen and sulfur dioxide, over Fe- and Co-containing catalysts supported on zeolites and zirconia, as well as on structured honeycomb monoliths.

Conditions were found for facilitation of the conversion of nitrous oxide in the presence of Fe-containing zeolite catalysts by oxidants (NO, SO2, and O2). The results were interpreted in the framework of a mechanism involving decomposition of N2O. The effect of NOx on the reduction of nitrous oxide by C3-C4 alkanes was established.

We have shown that conversion of nitrogen(I,II) oxides in reduction by carbon monoxide and light C1, C3–C4 alkanes in the presence of nanodispersed [Pt(Pd)-Au]/HY catalysts is determined by the reagent activation routes in an oxidizing/reducing atmosphere.

Experimental data on the lattice parameter, thermoelectric power, and microhardness of PbTe〈In〉 crystals and the conversion fromp- to n-type with increasing indium content can be interpreted under the assumption that the indium in PbTe〈In〉 has variable valence: 2In2+ ↔ In+ + In3+. A crystal-quasi-chemical model is proposed for defect formation in PbTe〈In〉: the incorporation of In+ into octahedral interstices and In3+ into tetrahedral interstices of the close packing of Te atoms, accompanied by In2Te3 precipitation.

Samples of zirconia doped with transition metal (Cr, Co, Ce) oxides, and also rhodium-promoted and Fe-containing zeolites of different structural types, were studied by NH 3 -TPD and IR spectroscopy. The various samples were analyzed with respect to their catalytic performances in deNO x reactions, in particular the selective catalytic reduction of NO (N 2 O) using hydrocarbons as reducing agents (HC SCR). Bifunctional zeolite- and ZrO 2 -based catalysts exhibited high activity in the SCR of nitrogen(I, II) oxides to dinitrogen due to the combination of the surface redox and acidic properties exhibited by these materials.