Gas-phase hydroformylation of propylene on Ru/SiO2 catalysts

Ru/SiO₂ catalysts prepared by reduction of supported RuCl₃·xH₂O are active in gas-phase hydroformylation of propylene at low pressure (ca. 0.3 MPa) of H₂+CO+C₃H₆ mixtured and show unexpectedly high selectivity towards unbranched oxo-products. Data concerning the effect of electronic state and dispersity of Ru on their catalytic behavior have been obtained.

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Ru/SiO₂, RuCl₃·xH₂O, (0,3 ) - . .

     

A study of complexation of chloral hydrate with heteropoly anions having various structures

¹H NMR was applied to study the interaction of chloral hydrate in deuterionitrobenzene solution with tetrabutylammonium salts of the heteropoly acids (HPA) belonging to five structural types: Keggin (H₃PW₁₂O₄₀, H₃PMo₁₂O₄₀, H₄SiW₁₂O₄₀), Dawson (-H₆P₂W₁₈O₆₂, -H₆P₂Mo₁₈O₆₂, -H₄S₂Mo₁₈O₆₂), H₆P₂W₂₁O₇₁(H₂O)₃, H₆As₂W₂₁O₆₉(H₂O), and H₂₁B₃W₃₉O₁₃₂. The surface of the HPA anions is nonuniform in acid-base properties. A general rule for all HPA was found, namely, that the HPA acidity increases with a decrease in the specific anion charge (per W or Mo atom).     

Palladium hydrogenation catalyst based on a porous carbon material obtained upon the dehydrochlorination of a chloro polymer

The applicability of a porous carbon material obtained as a result of the “chemical” dehydrochlorination of chlorinated polyvinyl chloride as a support for palladium hydrogenation catalysts was demonstrated. The efficiency of the catalyst was evaluated in the liquid-phase reactions of nitrobenzene hydrogenation and chlorobenzene hydrodechlorination. Although the specific activity of the catalyst was lower by a factor of 3–4 than that of the samples based on Sibunit and carbon nanotubes, the complete conversion of the initial compounds with the selective formation of end products under mild conditions was achieved at a relatively low palladium content (1.5%).     

Kinetics of sorption of poly(ethylene glycols) of various molecular masses by globular carbon

The kinetics of adsorption of poly(ethylene glycols) with molecular masses in the range 300–15000 from aqueous solutions by globular carbon with different radii of curvature of particles is studied. The kinetic adsorption coefficients of poly(ethylene glycols) are calculated. The dependences of the kinetic absorption coefficient on adsorbent dispersion and molecular mass of poly(ethylene glycol) are discussed.     

The Role of the Stage of Metal Complex Deposition on Support in the Properties Formation of Supported Platinum Catalysts

Kinetics and Catalysis - The subject of this review is related to the development of research on the mechanism of interaction of platinum complex compounds, primarily, H2[PtCl6], with alumina...     

Synthesis of Mg<Superscript>2+</Superscript>-, Al<Superscript>3+</Superscript>-, and Ga<Superscript>3+</Superscript>-containing layered hydroxides and supported platinum catalysts based thereon

The effect of the cationic composition of MgAl(Ga) layered double hydroxides on the structure, texture, and acid–base properties of related oxide supports for platinum catalysts has been investigated. As gallium is progressively substituted for aluminum in the mixed oxide, the properties of the support change only slightly, while the activity of the Ga–Pt catalysts in propane conversion increases, the propylene selectivity remains high (99%), and C–C bond hydrogenolysis is hampered.     

Influence of a doubly charged cation nature on the formation and properties of mixed oxides MAlO x (M = Mg2+, Zn2+, Ni2+) obtained from the layered hydroxide precursors

Influence of the nature of a doubly charged cation in the layered double hydroxides (LDH) on the conditions of formation and properties of mixed oxide phase MAlO _x (M = Mg²⁺, Zn²⁺ and Ni²⁺), its ability to reconstruct the structure of the original precursor under contact with water has been studied. Hydrotalcite-like compounds and corresponding oxides with different M²⁺: M³⁺ ratio were investigated by XRD, TEM, TG-DTG-DTA, ²⁷Al NMR, N₂ adsorption, and differentiating dissolution. It has been found that the nature of the cation M²⁺ influences the conditions of LDH thermal decomposition, structural and textural characteristics of the formed mixed oxides. The obtained data can be used to synthesize the oxide supports with desired acid-base and adsorption properties.     

Fundamental Technological Approaches to the Synthesis of Carbon Sorbents for Medical and Veterinary Applications

Russian Journal of General Chemistry - Some approaches to the synthesis of various modified carbon sorbents developed at the Laboratory of Synthesis of Functional Carbon Materials, Institute of...     

Preparation of Polyoxometalate-Stabilized Colloidal Solutions of Palladium Metal and Catalysts Supported on Them

Sols containing Pd(0) clusters with polyoxo anions are prepared by the reduction of colloidal solutions of polyhydroxo complexes of Pd(II) in the presence of Mo(VI), W(VI), V(V), and Nb(V) polyoxo anions. The cluster sizes varied within the limits of 1–10 nm depending on the nature of the polyoxo anion. The stability of sols toward coagulation depends on the ratio between the palladium and polyoxo anion amounts in solution and on the composition of the solvent. Supported Pd catalysts are obtained by the adsorption of particles from sols; Pd can exist in these catalysts as individual particles or associates or form filamentary structures.     

Interaction of nickel hydroxocarbonate,ammonium paramolybdate,and ammonium metatungstate under mechanical activation

The interaction of nickel hydroxocarbonate, ammonium paramolybdate, and ammonium metatungstate (Ni: Mo: W = 3: 1: 1) is reported. Under mechanical activation conditions, nickel hydroxocarbonate particles undergo comminution and ammonium paramolybdate and ammonium metatungstate particles soften and aggregate. It is demonstrated by DTA, X-ray diffraction, and IR spectroscopy that heat treatment of the mechanically activated mixture at 400–450°C yields the salts NiMoO₄ and NiWO₄.