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1.
By chemical trapping, an acyl species has been evidenced in the oxidation of alcohols to carboxylate on an alumina surface. A possible reacton scheme is discussed.
. .
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2.
The influence of the hydrothermal treatment of stabilized and nonstabilized Y zeolites on the location of Cr and Ni cations was tested. A significant influence of the above treatment was found.
Cr Ni. .
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3.
Monolithic supported platinum catalysts were investigated with respect to their hydrogenation and dehydrogenation activity towards benzene and cyclohexane, respectively, between 250° and 350°C. Conversion of benzene to cyclohexane is optimal for the volume ratio H2/Bz=5 at lower temperatures. In the cyclohexane dehydrogenation reaction, high temperatures, associated with lower N2/Cy ratios, are beneficial. No byproducts were observed in the two reactions.
, , 250 °C 350 °C. H2/=5. N2/ . .
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4.
Variations of acid-base properties on catalyst surface when modifying V–Mo–O catalyst by various additives changes the reaction course and the catalyst activity.
- V-Mo-O .
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5.
A kinetic method of freezing out free radicals combined with recording ESR spectra was used to study the HCl effect on the partial oxidation of methane over SiO2. This effect is ascribed to the surface modification of catalyst.
HCl SiO2. .
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6.
Langmuir-Hinshelwood type mechanisms with competitive adsorption are suggested to be more typical for metal catalysts, since, unlike on oxide systems, oxidizable substance and molecular oxygen can be adsorbed on the same (reduced) active sites. Therefore, multiple steady states and critical phenomena are more characteristic for catalysis on metals.
, - , , () . .
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7.
Five series of Pt–Pd/C catalysts were prepared with different total metal loading and different atomic composition in Pt and Pd. The activity in electrooxidation of hydrogen were measured for all these catalysts. Electrooxidation of hydrogen is a structure insensitive reaction on platinum and a structure sensitive reaction on palladium. For bimetallic catalysts, curves of activity as a function of the composition of the catalyst can exhibit a maximum. Yet, metal loading can alter the atomic composition at which activities are maxima.
Pt–Pd/C Pt Pd. . - - . . , .
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8.
Effect of solvents on photochemically induced metathesis of pentene-2 by W(CO)6 has been investigated. Structure of the catalyst and a reaction mechanism are proposed.
-2 W(CO)6. .
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9.
Water soluble analogues of aluminium and cobalt heteropolymolybdates have been shown as possible precursors of active sites for thiophene hydrodesulfurization along with other molybdenum compounds. For the characterization of the catalysts Raman spectroscopy has been applied, and the catalytic activity of the samples is discussed.
. .
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10.
    
- -Al2O3 -Al2O3. , .
In order to study the interaction of platinum with the support in mono- and bimetallic platforming catalysts based on -Al2O3 and -Al2O3, we have investigated the possibility of formation of a chloroaluminiumplatinum complex. The samples were treated with acetylacetone for 6 hrs and a platinum-alumina complex was detected colorimetrically. According to the data, the presence of a complex on mono- and bimetallic catalysts depends on the nature of the support.
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11.
Thermogravimetry and simultaneous DTA were used to investigate the phenomena of adsorption, desorption and surface reactions on solid catalysts. The measurements were carried out with NaX and X-type ion-exchanged zeolites and silica-alumina gels (Ketjen) treated with sodium hydroxide in the presence of carbon dioxide. On the basis of the quantitative results it is possible to give an interpretation of the surface phenomena and to establish the existence of various active centres on the surfaces of the catalysts. In the case of the adsorption of carbon dioxide on X-type zeolites, the quantity of carbon dioxide adsorbed is much smaller on ion-exchanged zeolites than on NaX.
Zusammenfassung Thermogravimetrie und simultane DTA wurden zur Untersuchung der Adsorptions-, Desorptions-Erscheinungen und Oberflächenreaktionen an festen Katalysatoren eingesetzt. Die Messungen wurden and NaX und Zeolithen des Typs X sowie an Silika-Aluminiumoxidgelen Ketjen durchgeführt, welche mit Natriumhydroxid in Gegenwart von Kohlendioxid behandelt worden waren. Aufgrund der quantitativen Ergebnisse ist es möglich eine Deutung der Oberfiächenerscheinungen zu geben und die Existenz verschiedener aktiver Zentren an der Katalysatorenoberfläche nachzuweisen. Im Falle der Adsorption von Kohlendioxid an Zeolithen des Typs X ist die Menge des adsorbierten Kohlendioxids am Ionenaustauscher viel niedriger als am NaX.

Résumé Application de la TG et de l'ATD simultanées à l'étude des phénomènes d'adsorption, de désorption et de réactions de surface sur des catalyseurs solides. Les mesures ont été effectuées avec des zéolites échangeuses d'ions de type NaX et X ainsi qu'avec des gels Ketjen silice-alumine traités par NaOH en présence de CO2. Les résultats quantitatifs permettent de donner une interprétation des phénomènes de surface et d'établir l'existence de divers centres actifs à la surface des catalyseurs. Dans le cas de l'adsorption de CO2 sur les zéolites de type X, la quantité de CO2 adsorbé est beaucoup plus faible que sur les zéolites de type NaX.

DTA , . - NaX X - « », . . X, - , NaX.
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12.
It is shown that the oxidative condensation of ethane on CoMo/-Al2O3 catalysts is in principle possible. The conceivable paths of this reaction are analyzed.
- .
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13.
The influence of the addition of pyrite and mechanical activation on an oxidative decomposition of chalcopyrite was studied. The course of the thermoanalytical curves and X-ray identification of the products showed that addition of pyrite affects mainly the endothermic processes taking place in region of low temperatures but does not significantly influence the temperature of CuSO4 formation and its content in the products of decomposition. Changes in fine and superfine structure of chalcopyrite brought about by mechanical activation at grinding cause the complex of exothermic oxidative reactions to proceed at temperatures as much as 180 deg lower than for a non activated sample. The endothermic effect of these oxidation reactions become more marked and the proportion of CuSO4 in the products of the oxidative decomposition increases significantly.
Zusammenfassung Am oxidativen Zerfall von Chalkopyrit wurde der Einfluss der Zugabe von Pyrit sowie der mechanischen Aktivierung untersucht. Der Verlauf der thermoanalytischen Kurven und Röntgendiffraktionsanalyse der Produkte zeigten, dass die Zugabe von Pyrit hauptsächlich die sich bei niedrigeren Temperaturen abspielenden endothermen Prozesse beeinflusst, nicht aber die Bildungstemperatur von CuSO4 sowie dessen Gehalt in den Zersetzungsprodukten. Durch mechanisches Aktivieren mittels Feinmahlen hervorgerufene Veränderungen in der Fein- und Superfeinstruktur lassen die Gesamtheit der exothermen oxidativen Reaktionen bei Temperaturen ablaufen, die etwa 180 Grad unterhalb derer für unaktivierte Proben liegen. Die endotherme Färbung dieser Oxidation wird eindeutiger und der Anteil von CuSO4 in den Produkten des oxidativen Zerfalles nimmt eindeutig zu.

. , . , , - , 180° , . - .
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14.
The nature and rate of coke deposited on mono-and bimetallic reforming catalysts have been studied for normal heptane reforming. For bimetallic catalysts it has been shown that coke deposition is less extensive than on monometallic catalyst, depending on the degree of polymerization and the type of bimetallic catalyst.
-. , , , .
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15.
Formation of alkenylcarbenium ions has been proved during transformation of allyl alcohol on zeolite HZSM-5.
HZSM-5.
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16.
The activity and selectivity of copper-iron catalysts for the synthesis of light alcohols from carbon monoxide and hydrogen were studied. The suitable ratio of copper to iron and optimal chemical composition of the catalyst were determined.
- . .
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17.
Exchange kinetics of some transition metal ions on tin(IV) arsenosilicate has been studied at various temperatures under particle diffusion controlled conditions. Various useful kinetic parameters such as self-diffusion coefficient (Do), energy of activation (Ea) and entropy of activation (S*) have been calculated and compared with other similar materials.
(IV) . , (DO), (Ea) (S*), .
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18.
During hydrocarbons reactions over Pt/Al2O3 the catalyst is covered by coke. It is accepted that coke formation occurs on metal and acid sites. During normal heptane and methylcyclopentane reforming it was found that the nature and the rate of coke deposited on the catalyst surface was not same, depending on the structure of the hydrocarbon feed.
Pt/Al2O3 . , . , - .
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19.
The catalytic reaction between hydrocarbons and carbon dioxide, e.g. CH4+ +CO22CO+2H2 and C6H6CH3+CO2C6H6+2CO+H2, has been investigated over various metallic catalysts under atmospheric pressure. In general, Rh–Al2O3 catalyst was found to be excellent in activity and selectivity. The reaction rates were moderately dependent on the pressure of carbon dioxide, whereas it was little influenced by the pressure of hydrocarbon.
, ., CH4+CO22CO+2H2 C6H5CH3+CO2C6H6+2CO+X2, . , Rh–Al2O3 . , .
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20.
The uptake of sulfur reduces the overall activity of PtMo/Al2O3 and enhances that of CoMo/Al2O3 in conversion of cyclohexanol. Significant changes in selectivity indicate the existence of different active sites of the initial catalyst for hydro-dehydrogenation and dehydration. The differences in catalytic activity expressed in terms of overall TOF decrease with increasing sulfur treatment like for Ru and Ir promoted catalysts.
PtMo/Al2O3 CoMo/Al2O3. - . Ru .
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