The formation of novel copper-, nickel-, cobalt-, and zinc-containing alumina catalysts prepared by the interaction of water with indium-and gallium-modified aluminum alloys containing copper, nickel, cobalt, and zinc is studied using the thermal methods of analysis, XRD, adsorption methods, TPR, IR spectroscopy, and XPS. The samples that were not subjected to thermal treatment are shown to contain pseudoboehmite (PB) and bayerite (B) as well as the intermetallides (aluminides) of copper, nickel, or cobalt, the In, Al, Zn, and Cu metals, the oxide (in the case of the copper alloy) or hydroxyaluminate (in the case of the zinc ahoy) of the metal. With increasing concentration of an active component, the relative content of B increases and that of PB decreases. During thermolysis, PB and B are transformed into various low-temperature modifications of Al2O3 and zinc hydroaluminate is converted into a solid solution ZnO-Al2O3. Under the oxidative conditions at temperatures below 550 degrees C, the In, Zn, and Cu metals form In2O3, ZnO, and CuO, respectively, while at elevated temperatures (similar to 1000 degrees C), the high-temperature modifications of Al2O3 and the aluminum spinels (of zinc, copper, or nickel) appear. Under the reductive conditions at temperatures below 690 degrees C, In2O3 is transformed into indium metal, Co3O4 and cobalt-containing compounds are converted to beta-Co, CuO is transformed into Cu, and nickel-containing compounds yield metallic Ni. According to XPS data, the phase of gallium was not found in any sample. The Lewis acidity (measured using pyridine as a probe) in the activated copper-containing catalysts is a function of the surface concentration of copper, indium, and gallium. Copper-, nickel-, cobalt-, and zinc-containing catalysts have a nonuniform pore structure and a developed surface area, which slightly changes in the wide temperature range (120-600 degrees C). With increasing metal content, independently of its nature, the specific surface areas of the catalysts drop nearly in the same way.

The formation of the bulk and surface of a new generation of oxide alumina catalysts, prepared by the interaction of metallic aluminum (Al-met) activated with Ga and In with water, is studied by XRD, thermal analysis, adsorption, and IR spectroscopy. At the stage of hydroxide formation, pseudoboehmite (PB) and bayerite (B) are produced, with the ratio between these phases dependent on the temperature of the interaction between Al-met and water and on the concentration of the activating additive. Thermolysis of PB and B leads to various low-temperature modifications of Al2O3. The In concentration at the surface is lower than in the bulk. Unlike indium, gallium is uniformly distributed between the surface and the bulk and cannot be revealed as a separate phase by XRD. The oxide alumina catalysts exhibit a developed surface area (up to 320 m(2)/g) and diverse porous structures. Three types of non-associated OH groups, characterized by the different number of adjacent Al atoms, as well as OH groups with a strong hydrogen bond are found at the surface. Lewis, but not Bronsted, acidic properties (revealed by pyridine adsorption) are inherent to the catalyst surface. The number of Lewis acid sites increases from 1.0 to 2.2 mu mol/m(2) with an increasing concentration of activating agents from 2 to 20 wt %.

A new method is developed for the synthesis of an adsorbent and support with a high, regulated surface area (up to approximately 300 m2/g) and a high mechanical strength (40 - 70 MPa). The surface area retains the value of 35 - 90 m2/g even after high temperature treatment (approximately 1000-degrees-C). The process of the surface area enhancement from 2 - 4 to 300 m2/g involves one or two stages: hydration in neutral or basic media and acid treatment. The effect of different parameters (treatment temperature and duration, reagent nature, and acid component concentration) on the surface area is evaluated. Using XRD, IR, TGA, DTA, and chemical analysis data, consideration is given to the reactions which are related to the evolution of the phase composition and development of the surface area in the course of the formation of the new adsorbent and support. The promising aspects of application of the new material in catalysis are discussed.

Using x-ray phase analysis, DTA, DTG, and temperature-programmed reduction, we have studied the phase composition and formation of cobalt-copper cement catalysts obtained by chemical mixing of hydroxocarbonates of cobalt (CoHC) and copper (CuHC) with the aluminocalcium cement talyum, consisting of CaAl2O4 and CaAl4O7, in an aqueous ammonia medium. We have shown that when the components are mixed, exchange reactions occur with development of new phases of cobalt and copper hydroxoaluminates, calcite, gibbsite, Cu(OH)2, CuO. We found that CaAl2O4 is more reactive than CaAl4O7. We have obtained data on the change in the phase composition upon thermolysis and reduction in H-2.

The structure of synthesized cobalt hydroxoaluminate (CHA) and course of thermolysis and reduction were investigated by XPA (including high-temperature x-ray diffraction), thermal chromatography, DTA, DTG, IR, and UV spectroscopy. It was shown that the activity the products of reduction activation of CHA in synthesis of hydrocarbons from CO and H-2 is a function of the temperature of reduction and synthesis. It was concluded that hydrocarbons are synthesized on Co/CoAl2O4. The production of CHA are active in the same reduction temperature range as the previously studied cobalt cement catalysts.

X-ray phase analysis, thermal analysis, and diffuse reflection electronic spectroscopy have been used in studying the formation of the catalytic system ZnCl/sub 2///gamma/-Al/sub 2/O/sub 3/. It has been shown that interaction of the salt component with the support leads to the formation of a complex multiphase system including excess zinc-containing phases with various compositions, structures cross-linked to the surface, and spinel-type structures formed by insertion of zinc ions into the surface layers of the lattice of the support. The kinds of phases that result from this interaction depend on the conditions of catalyst formation and on the phase composition of the support. The catalytic system does not contain and compositions that are fusible within the interval of temperatures investigated (20-500/degree/C).

X-ray phase analysis and thermal analysis have been used in an investigation of the structure and phase composition of catalytic systems consisting of ZnCl/sub 2/-NaCl and ZnCl/sub 2/-KCl on /gamma/-Al/sub 2/O/sub 3/ support, and also the genesis of these systems under the influence of temperature. It has been shown that the systems contain excess agglomerated salt phases, two-dimensional structures that are cross-linked to the surface, and bulk structures formed by insertion of metal ions into the crystal lattice of the support. At high temperatures, the sodium and potassium chlorides on the surface exist for the most part in isolation from the zinc-containing salt phases. Changes in the composition and structure of the zinc-containing phases play the predominant role in forming the catalytic systems. No melting effects have been found in these catalytic systems.

The phase composition, morphology, and other structural characteristics of a copper-zinc system prepared by the non-traditional method of mixing copper and zinc hydroxycarbonates in water-ammonia medium at 75/sup 0/C in stages of mixing, thermal decomposition, and activation in an atmosphere of hydrogen, and the catalytic properties in the reaction of low-temperature conversion of carbon monoxide with water vapor were studied. A chemical reaction with formation of a mixed copper and zinc hydroxycarbonate takes place during mixing of the starting components. It was found that samples prepared by thermal decomposition and reduction of a compound with a structure and composition close to aurichalcite (Zn, Cu)/sub 5/(CO/sub 3/)/sub 2/(OH)/sub 6/, exhibit the highest activity. The x-ray amorphous state of a significant fraction of the copper in the reduced samples correlates with their catalytic activity.