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Metal oxide pillared interlayered clays (PILCs) possesses several attractive properties, such as constant high porosity with presence of both micropores and mesopores, thermal stability (up to 450°C), surface acidity and catalytic active components - metal oxide pillars. Thanks to these specific characteristics of PILCs they can be used either as catalyst or as catalyst support in a wide range of catalytic applications, including catalytic cracking processes. In this work Fe-pillared interlayered clays (Fe-PILCs) were obtained by intercalating trinuclear acetate hydroxy-iron (III) chloride between the layers of Na-exchanged montmorillonite with following calcination and characterization by different analytical techniques. Trinuclear acetate hydroxy-iron (III) chloride was chosen as pillaring agent because its cations are more stable in solution than traditionally used oligo(poly)hydroxy iron cations. X-ray diffraction data showed the increase of basal spacing of the material after calcination (up to 450ºC) indicating formation of thermally stable pillars between the clay sheets. N2 BET specific surface area was 320 m2/g, that is significantly higher compared tovalues (about 200 m2/g) for the traditional PILCs synthesized by alkaline hydrolysis route. Mössbauer spectroscopy displayed presence of superparamagnetic forms of iron and magnetite-like oxides, connected with aluminosilicate matrix. Obtained material was studied as catalyst for the cracking of higher hydrocarbons with composition of C11-C22. [ABSTRACT FROM AUTHOR]

In this study, investigation of the composition, structure and catalytic activity of the catalyst support based on Ni-Al mixed oxides was carried out. The possibility of controlling structural and acid-base properties of the layered double hydroxides (LDH) by varying the ratio of M2+/M3+ metal cations determines its use as catalyst support. Besides varying of anions in the interlayer space allows to regulate catalytic system activity in the reaction medium. The Ni-Al LDH support was prepared by coprecipitation method followed by conversion to Ni-Al mixed oxide in the reaction medium. According to the X-ray diffraction analysis, it was shown that the Ni-Al-based mixed oxide obtained with a specific surface area of 158 m2/g contains nickel oxide with a reduced lattice parameter related with the replacement of part of Ni2+ cations with Al3+, phase of mixed oxides of variable composition and amorphous phase. The replacement of Ni2+ by Al3+ in nickel positions is 16%. The crystallite size of the obtained oxide phases is 4 nm. The catalytic activity of Ni-Al mixed oxide was determined in the reactions of the conversion of higher alkanes of the C11-C22 composition, taken in equal proportions, at a temperature of 500°C and a feed to catalyst ratio of 30. According to the chromatographic analysis, alkanes and isoalkanes of composition C7-C14 were formed as catalytic products. Unsaturated compounds in the reaction products were revealed by IR spectroscopy method; the iodine value was 0.172. [ABSTRACT FROM AUTHOR]