R. G. Romanova

Catalytic dehydration of α-phenylethanol on the surface of aluminum oxides

The relationship between the acid–base properties of commercial and test samples of aluminum oxides and their catalytic activity in the dehydration of α-phenylethanol was studied. It was found that, in the dehydration of α-phenylethanol, the conversion of the alcohol and the yield of styrene on a catalyst depend on the concentrations of both Brønsted and Lewis acid sites. A hypothetical mechanism of the dehydration with the participation of coordinatively unsaturated aluminum atoms and bridging oxygen ions on the alumina surface was proposed.

Effect of Acid Modification on the Structure and Catalytic Activity of Aluminum Oxide

The effect of acetic acid introduced as modifying additive into active aluminum oxide on its structural characteristics is considered. A relationship is established between the structural characteristics, content and features of aprotic acid centers, and catalytic activity of the obtained catalysts in dehydration of methylphenylcarbinol.

The composition and thermal behavior of nanodispersed silica synthesized by micellar technology

Morphology, particle size, and thermal behavior of silicic acid synthesized as gel by micellar technology were determined. It was found that the micellar synthesis using a smaller-molecule solvent, organic acid with shorter hydrocarbon (hydrophobic) part, as surfactant and silicate with smaller-radius cation yields silica gel with smaller particle size and, as consequence, increases silica dispersity. The differential thermal analysis of the synthesized silica gel showed that for samples with lesser particle size the phase transition temperatures are decreased by about 30–100°C.

Influence of the phase composition of the support on the catalytic activity of bimetallic catalysts

The influence of the nanocrystalline structure of an aluminum-zinc spinel support on the catalytic activity of bimetallic Pt-Sn catalysts in dehydrogenation of 2-methylbutane was studied. The formation of the spinel structure in solid-phase reactions of aluminum and zinc oxides was examined.

Effect of the catalyst structure on the catalytic activity in dehydrogenation of 2-methyl butane

Calorimetry, thermogravimetry, X-ray diffraction analysis, and low-temperature adsorption of nitrogen were used to study the structure of bimetallic Pt—Sn catalysts on zinc–alumina spinel supports. The effect of the porous structure of the catalyst samples synthesized on their catalytic activity in dehydrogenation of 2–methyl butane was analyzed.

Isoprene manufacturing process on a new bimetallic (platinum-tin) catalyst

The influence of the reaction conditions on the characteristics of the one-step process of the dehydrogenation of 2-methylbutane or 2-methybutenes to isoprene in the presence of a new bimetallic (Pt-Sn) catalyst was studied. It was shown that this catalyst supported on a material with an optimal structure holds promise for use in the industrial-scale process for the manufacturing of isoprene via one-step dehydrogenation.

Thermodynamic parameters of the single-stage dehydrogenation of isopentane to isoprene

From the results of experiments with platinum-containing catalysts operating in the steady mode, adiabatic changes in temperature in the course of 2-metylbutane dehydrogenation to monoolefins and isoprene were calculated. Dehydrogenation of 2-methylbutane and its mixtures with methylbutenes in the 500–600°C temperature range was simulated with varying the concentrations of 2-methylbutane, methylbutenes, hydrogen, and water, the conversion, and the selectivities with respect to both isoprene and methylbutenes. The most suitable reactor designs with intermediate heating of the reaction mixture were suggested.

Acid-base surface properties of binary systems based on aluminum and zirconium oxides

The formation of a hydroxyl cover and acid-base sites on the surfaces of electrochemically coprecipitated binary aluminum and zirconium oxides is studied. It is found using IR probe spectroscopy that the surface electron-donor and electron-acceptor properties of binary aluminum-zirconium oxide systems depend on the synthesis conditions.

A Study of Composition and Structure of Aluminozirconium Hydroxides Obtained by Coprecipitation in Membrane Electrolyzer

Fundamental aspects of formation of aluminum and zirconium hydroxides in their coprecipitation under the action of products of electrode reactions in a membrane electrolyzer were studied. The influence exerted by precipitation conditions (temperature and pH value) on the phase composition and porous structure of coprecipitated systems was analyzed.

Changes in the Composition, Structure, and Activity of Catalysts in Hydrogenation of Diene Hydrocarbons of the C5-C9 Fraction of Pyrolysis Naphtha

A comparative study was performed of changes in the composition, structure, and catalytic activity of catalysts in selective hydrogenation of C5-C9 fraction of pyrolysis naphtha. The main reasons for catalyst deactivation in the course of industrial exploitation were considered.