Alumina-grafted materials were prepared by postsynthesis alumination of mesoporous SBA-15 silica in an aqueous solution of aluminum chlorhydrol. Prepared samples were characterized by nitrogen adsorption, scanning electron microscopy, X-ray powder diffraction, and (27)Al magic-angle-spinning NMR. The successive grafting of alumina on SBA-15 leads to a gradual filling of the corona surrounding the mesopores. As a consequence smoothing of the mesopore surface takes place. The in-depth analysis of nitrogen adsorption data proves that the alpha s method affords real values of the structure parameters, while the Kruk, Jaroniec, and Sayari (KJS) procedure based on the BJH algorithm provides only effective data corresponding to cylindrical mesopores of smooth geometrical surface. The quantification of the roughness of the SBA-15 mesopore surface based on the comparison of data obtained from the alpha s plot and KJS method was carried out.

The role of the type of acid site (Broensted vs. Lewis) on the activity and selectivity of molecular sieve catalysts was investigated in ferrocene and toluene acylation. H-, Zn-, Fe-, Al- and La-forms of zeolite Beta, USY and mesoporous molecular sieves (Al)MCM-41, (Al)SBA-15 were tested. It was observed that addition of metal cations acting as Lewis acid sites can increase the acidity of various molecular sieve catalysts. No general relationship between the type of cation and conversion of individual substrate was found. While the highest activity in ferrocene acylation was observed after addition of Zn, in the case of toluene acylation Al-forms of catalysts were the most active. The results indicate that the acid strength of cationic Lewis sites controls their activity in acylation reactions.

A series of samples of MCM-41 silica was synthesized using surfactant blends of 1-alkyl-3-methylimidazolium and alkyltrimethylammonium salts or blends of two different 1-alkyl-3-methylimidazolium salts (alkyl denotes octyl or hexadecyl) as structure-directing agents. The precipitation of solid particles from a homogeneous water solution of sodium metasilicate and surfactant blend was achieved by lowering the pH due to the hydrolysis of ethyl acetate added. The molecular sieves were characterized by scanning as well as transmission electron microscopy, X-ray powder diffraction, and nitrogen adsorption using a proper nonlocal density functional theory approach for calculations of the textural parameters. All the prepared silicas were of MCM-41-type; they differ in the integral breadth of the pore size distribution curve and the presence of secondary mesopores. The best quality MCM-41 silica of spherical particle morphology was synthesized by using of optimized blend of hexadecyltrimethylammonium bromide and 1-methyl-3-octylimidazolium chloride. The results obtained showed that spherical particles are composed of domains of perfectly ordered hexagonal porous structure. Some samples prepared by using 1-alkyl-3-methylimidazolium salts featured a narrow pore size distribution. However, they contained a small volume of secondary mesopores. AbbreviationsS BET BET surface area, m 2 /g S ME cumulative mesopore area, m 2 /g V ME cumulative mesopore volume, cm 3 /g D ME mesopore mode diameter, nm D ME integral breadth of the mesopore distribution curve, nm V SEC volume of secondary mesopores, cm 3 /g V TOT total pore volume, cm 3 /g W ME mesopore size calculated using equation (1), nm

A Ru -TsDPEN (RuCl[(1S,2S)-N-p-tosyl-1,2-diphenylethylendiamine]pcymene) catalyst of the Noyori type was immobilized in the channels of MCM -41 molecular sieve functionalized by (3 -aminopropyl)triethoxysilane (APTES). The resulting compound was tested as a catalyst for the hydrogenation of 1-methyl-3,4-dihydroisoquinoline (MIQ) under laboratory conditions using an azeotropic mixture of formic acid and triethylamine (5:2) as the source of hydrogen and compared to the results acquired in the corresponding system.

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