Реферат: Ceramometals synthesized from aluminum-containing powders have been known for quite a long time [1–3]. Synthesis of such materials is based on the ability of aluminum to be partially oxidized by water under hydrothermal treatment (HTT) conditions with subsequent hydrolysis of the oxidation products, their precipitation and crystallization on the surface of metal particles [4]. Crystallization at the con-tact sites of metal particles leads to their cementation into a porous monolith. There are several main approaches to the synthesis of porous ceramometals and their application as supports and catalysts. a) Synthesis of Al2O3/Al ceramometals from powdered aluminum with subsequent deposition of the active component (AC) from a solution [5–11]. b) Incorporation of the AC into Al2O3/Al matrix via mixing the powdered AC as ox-ides or alloys with aluminum. Details of ceramometal synthesis are illustrated in Fig. 7.1 [5, 6]. Powders are charged into special molds, which allow access of water and withdrawal of the produced hydrogen. It is possible to vary features of the aluminum powder, temperature, pressure and time of HTT. The mold with the loaded powder is then subjected to HTT. Details of the process are reported in [4, 7–10]. A firm porous monolith is produced upon HTT; it is taken out of the mold and calcined. Size and form of the resulting monoliths can be widely varied depending on the design. 7.1 Ceramometal supports and catalysts based upon Al2O3/Al 7.1.1 Influence of the nature of aluminum powder on the microstructure, texturaland mechanical properties of Al2O3/Al ceramometals In Al2O3/Al ceramometals aluminum is evenly distributed in the oxide matrix. A typical relief of the fracture face of Al2O3/Al cermet prepared by oxidation of aluminum powder by water at 100 °C followed by calcination in air at 550 °C is shown in Fig. 7.2 [11]. Aluminum particles are covered by a porous oxide film. Analysis of the ceramometal macrostructure (Fig. 7. 3a–c) shows that it substantially depends on the type of the aluminum powder. The loosest packing of the monoliths is typical for ceramometals produced from PAP-2 powder. Averaged characteristics of the obtained materials are also very different (Table 7.1) [11]. The average macropore diameter is determined by the Darcy method

Библиографическая ссылка: Sadykov V.A. , Tikhov S.F. , Isupova L.A.
Ceramometal Supports and Catalysts Prepared through Hydrothermal Treatment of Al-Containing Powders
Глава монографии Heterogeneous Catalytic Redox Reactions. Fundamentals and Applications. – De Gruyter., 2019. – C.137-157. – ISBN 9783110585865. DOI: 10.1515/9783110587777-007 WOS OpenAlex

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