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With an increasing population, up to 9 billion, and oil as well as gas stocks being finite, we should reconsider sustainable raw materials, as provided annually by plants and trees and covered by the collective term biomass, as chemical feedstock. Carbohydrates are the

The effect of high temperature calcination and steaming on iron-containing zeolite was studied. Iron was introduced by sublimation of FeCl₃. FTIR measurements clearly show the disappearance of Broensted acid sites upon such treatments. This is attributed to a reaction between small occluded Fe oxide clusters obtained after initial low temperature calcination and the zeolite protons to give cationic Fe species compensating the negative zeolite charge. High temperature calcination and especially steaming considerably increase the catalyst activity in nitrous oxide decomposition. The two treated catalysts exhibit a higher apparent activation energy than the original sample. This high apparent activation energy is compensated by a high pre-exponential factor. In Fe/ZSM5 the activity mainly derives from small Fe oxide clusters, while upon treatment more active cationic species are generated. The kinetic parameters point to a stronger Fe–O bond for the latter case.

The semi-empirical Method of Interacting Bonds was used in the present work to clarify the mechanism of the title process. Various single crystal planes of Pt, Rh, Ir, Fe, and Re were examined with respect to the stability of the adsorbed NH_n species (n = 0, 1, 2, 3); to the reactivity of NH_n (n = 0, 1, 2) species towards adsorbed hydrogen atoms; and to the possibility of proceeding the combination reactions between two NH or two NH₂ particles resulting in the formation of gaseous H₂ and N₂ molecules. All the surfaces studied were found to form readily the stable NH species. The principal difference between Pt, Rh, Ir single crystal planes, on which the reaction exhibits rate oscillations, and Fe, Re surfaces, which do not show an oscillatory behaviour, is that the combination reaction of NH species can easily proceed in the former case, but this reaction is not allowed thermodynamically on the latter surfaces. This result is consistent with an earlier suggested mechanism for the oscillatory behaviour that attributes the surface wave propagation to the intermediate formation of NH species. Stable NH₂ species can be formed on Re and Fe surfaces, whereas the noble metal surfaces can form weakly stable NH₂ particles at the very edge of their existence region. The combination reaction between two NH₂ species is endothermic in all cases.

Detailed studies of the coadsorption of oxygen and carbon monoxide, hysteresis phenomena and oscillatory reaction of CO oxidation on Pd(110) and Pd tip surfaces have been carried out with the molecular beam (MB), field electron microscope (FEM), temperature programmed reaction (TPR) and X-ray photoelectron spectroscopy (XPS). It has been found that the occurrence of kinetic oscillations over Pd surfaces is associated with periodic formation and depletion of subsurface oxygen (O_sub). Transient kinetic experiments show that CO does not react chemically with subsurface oxygen to form CO₂ below 300 K. It has been found that CO does react with an atomic O_ads/O_sub state beginning at temperature ~150 K. Analysis of Pd tip surface with a local resolution of ~20 Å shows the availability of a sharp boundary between the mobile CO_ads and O_ads fronts.

X-ray, TA, IRS, TEM and BET techniques were used to study the effect of mechanical treatment in a centrifugal planetary ball mill EI 2´150 and in a continuously operating vibration ball mill VCM-25 on physicochemical properties of powdered iron oxide of different prehistory, as well as on the properties of produced granulated supports and catalysts. The influence of structure-forming additives and electrolyte was discussed. The influence of the method used for introduction of the active component on the catalyst properties for complete oxidation of butane and CO was established.

The NMR microimaging is used for the first time as an in situ method to study two model three-phase heterogeneous catalytic reactions with strong exothermicity. It is shown for the α-methylstyrene hydrogenation that in the course of the reaction, two domains coexist inside the catalyst grain which differ in the liquid phase content. The 2D maps of the liquid distribution in the course of this reaction are obtained. The reaction of the hydrogen peroxide decomposition at moderate activity of the catalyst and the H₂O₂ concentrations in the range of (0.03–3) M is shown to occur only in a thin layer near the catalyst surface. The influence of the medium inhomogeneity on the behaviour of the Belousov – Zhabotinsky chemical oscillator reaction is investigated as well.

Relationship of structure and surface properties of modified titanium dioxides, prepared by alkoxide method using derivatives of phosphoric acid as precursors, with their catalytic performance in the reaction of ethylene glycol ethoxylation was investigated. It was found, that such catalysts are mono-phase, nanocluster ones with anatase structure, and have uniform narrow pore distribution. Catalysts prepared using the amidophosphite precursors provide high catalytic activity due to the high surface acidity, and high selectivity of diethylene glycol formation due to the "sieve effect" and concert acid-base mechanism of ethylene oxide addition.

Experimental studies were focused on the feasibility of utilization of hydrocarbons diluted with inert gases (such as associated oil gases) during the synthesis of nanofibrous carbon. The carbon yield and catalyst lifetime were studied regarding the initial reaction mixture parameters. Varying the composition of the initial gas mixture, it is possible to control textural characteristics of the resulting carbon product.

The influence of porous structure and surface acid-base properties of γ-Al₂O₃, prepared by means of aluminate-nitrate and electrochemical methods, on its catalytic activity in the process of α-phenylethanol dehydratation has been studied. It was shown, that activity of catalyst depends on the predominating diameter of pores. The methods of changing the porous structure of γ-Al₂O₃ with the purpose of increasing its catalytic activity were considered. Thermal or hydrothermal treatment of active aluminium oxide allows to obtain the porous structure, providing the maximum activity of catalyst in the process of α-phenylethanol dehydratation. It was also shown, that conversion of α-phenylethanol and selectivity are determined by the surface concentrations of Broensted and Lewis acid centres. The rate of catalyst deactivation (coke formation) is proportional to the concentration of base centres. The influence of content of sodium cations on the acid-base properties and activity of catalyst was determined. Purification of used γ-Al₂O₃ from sodium cations results in the catalyst, having the maximum catalytic activity.

The metal (stainless steel) porous "metal-rubber" monolith-supported Pt, Pd, Pt–Rh and Pd–Rh catalysts are tested in the process of complete oxidation of hydrocarbons. At stoichiometric and higher oxygen content practically complete conversion of model hydrocarbon occurred at 380 °C on all catalysts. At these temperatures the catalysts work in outward diffusive area. At the oxidant to fuel ratio lower than stoichiometric the maximal conversion of hydrocarbon is reached at lower temperatures (250 °Ñ). In complete hydrocarbon oxidation steady work of platinum catalyst is possible, if the content of sulphur in hydrocarbon does not exceed 0.3 % mass. These catalysts may be used for preparing a gas sample in oxygen sensors.