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Gold nanospecies produced by a historically inspired two-liquid phase system were immobilized on plate-like mesoporous silica, SBA-15, functionalized with mercaptopropyl groups by a post-synthesis method, and the resulting materials were tested in the oxidation of cyclohexene with molecular oxygen at atmospheric pressure. The main purpose of this approach was to compare the physicochemical properties and catalytic performance of these materials with those of previously reported related materials functionalized by in situ methods during synthesis. In addition, catalytic tests under ambient lighting and darkness and also in the presence and absence of the initiator tert-butyl hydroperoxide (TBHP) were carried out. The samples were characterized by chemical analysis, N2 adsorption/desorption, TGA, SEM, HRTEM, UV-vis spectroscopy and XPS. Gold nanoclusters and isolated gold atoms but no AuNPs were found in the catalysts (0.31–2.69 wt.% of gold). The XPS shows that nearly 60% of the -SH groups (1.33 wt.% of S) were oxidized to sulphonic groups upon gold immobilization. The AuNCs and isolated gold atoms evolved in the the reaction medium to form AuNPs. The activity of the samples was lower than that of the catalysts supported on related S-bearing SBA-15 functionalized in situ, which was attributed to their different Au/S ratios, which in turn regulated the evolutionary process of the gold species during the reaction. The catalysts turned out to be inactive in darkness, which evidences that the cyclohexene oxidation carried out at ambient illumination is actually photocatalyzed by the AuNPs formed in situ during the reaction. The TBHP initiator is required to obtain the activity in order to counteract the inhibitors of cyclohexene auto-oxidation present in the commercial reagent. On the other hand, no major differences in the selectivity among the different catalysts and reactions were observed, with 2-cyclohexen-1-one and 2-cyclohexen-1-ol resulting from the allylic oxidation as main products (selectivity of (one + ol) ~80% at a conversion ≥ 35%; one/ol~2). [ABSTRACT FROM AUTHOR]

Abstract Commercial Beta zeolite (Si/Al = 19) was treated with aqueous solutions of hexadecyltrimethylammonium (CTA) in the presence of NaOH or NH 4 OH to generate hierarchical porosity in the material. The combination of a basic media and surfactant (CTA) allows generation of mesoporosity while preserving the crystallinity and acidity of the parent Beta zeolite. In addition, characterization by XRD and TEM gave no evidence for the formation of segregated mesoporous phases. TEM and N 2 adsorption isotherms suggest the presence of substantial intracrystalline mesoporosity (average pore size of 3 nm) in the Beta zeolite crystals, which was more pronounced for samples treated with CTA/NaOH solutions. The concentration of total Brønsted acid sites was determined by pyridine adsorption, and it increased in the treated samples as compared with the parent Beta zeolite. The strongest Brønsted acid sites slightly increased for the CTA/NH 4 OH sample, while they decreased when ammonium hydroxide was replaced by NaOH. All these results indicate that the basic character (i.e. strength) of the aqueous solution affects the degree of the zeolite mesostructuring process. The activity of the treated samples in the isomerization-disproportionation (I-D) of m-xylene was related to the concentration of the strongest Brønsted acid sites. The treatment with sodium hydroxide or ammonia aqueous solutions led to an I/D ratio lower than that of the parent Beta zeolite, evidencing the benefits of the additional mesoporosity by enhancing the formation of the bulkiest bimolecular intermediate required to form disproportionation products. Graphical abstract Image 1 Highlights • Zeolite Beta containing intracrystalline mesopores has been obtained by a post-synthesis methodology. • Time and nature of alkaline solution affects the surfactant incorporation to generate mesoporosity. • Crystallinity and Si/Al ratio was preserved after hierarchical material was obtained by post-synthesis treatment. [ABSTRACT FROM AUTHOR]

This work reviews the origin of the current Instituto de Catálisis y Petroleoquímica (ICP, Institute of Catalysis and Petroleum Chemistry) that belongs to the Consejo Superior de Investigaciones Científicas (CSIC, Spanish National Research Council). The first papers on catalysis were published in Spanish scientific journals in 1908. In 1912, the first catalytic experiments were done in the research laboratories belonging to a new Spanish institution established in 1907, the Junta para la Ampliación de Estudios e Investigaciones Científicas (JAE, Council for Development of Studies and Scientific Researches), which was not dependent on the university. These laboratories were later integrated in the new Instituto Nacional de Física y Química (National Institute of Physics and Chemistry), opened in 1932 and located in a new building financed by the Rockefeller Foundation. In 1939, at the end of the Spanish Civil War (1936–1939), the JAE was abolished and replaced by CSIC. As a consequence of the reorganization process of the research institutes undertaken by CSIC, the Instituto de Química Fisica “Antonio Gregorio Rocasolano” (IQFR, Institute of Chemical Physics) was founded in 1946, which basically inherited the former National Institute of Physics and Chemistry, and on the very same premises. A new Catalysis Laboratory was established in 1953 in the IQFR under the leadership of Prof. Juan Francisco García de la Banda, which evolved through several steps to become finally an independent research center in 1975 under the name of Instituto de Catálisis y Petroleoquímica (ICP, Institute of Catalysis and Petroleum Chemistry). The ICP moved to its present premises in 1990. [ABSTRACT FROM AUTHOR]

Zn atoms have been incorporated into the STA-1 microporous framework (SAOframework type) for the first time. Pure Zn-containing STA-1 aluminophosphate has been obtained in the presence of either (S)-(−)-N-benzylpyrrolidine-2-methanol (BPM) or benzylpyrrolidine (BP) as structure-directing agent. Characterisation results have demonstrated that the organic molecules remain intact within the microporous framework after the hydrothermal treatment. The X-ray diffraction pattern has been indexed in the tetragonal space group I4m2 (a= 13.7828(1) Å and c= 21.9444(4) Å). Chemical analysis and 31P MAS NMR spectroscopy confirm the incorporation of ca. 4.5 Zn atoms per unit cell by isomorphous substitution of Al. This large-pore aluminophosphate has one of the lowest framework densities among the known zeolite structures, and is therefore of potential interest for applications in adsorption or catalytic processes involving bulky molecules. [ABSTRACT FROM AUTHOR]

Abstract: Several synthesis strategies used to obtain hydrothermally stable and highly active catalysts based on ordered mesoporous materials are reviewed in this contribution. It is experimentally observed that the use of zeolite precursors as building blocks of the mesoporous network yields the most stable materials. However, the nature of the mesoporous framework of these solids remains still unknown, and basic understanding of the assembling process of zeolite precursors and surfactants has not yet been achieved. Some key features of the whole process are explored, and examples that illustrate its chemical and structural complexity are provided. To cite this article: J. Pérez-Pariente et al., C. R. Chimie 8 (2005). [Copyright &y& Elsevier]

Partial esters of polyols such as glycerol, polyglycerols and sorbitol are nonionic surfactants used as emulsifiers in the food, detergents and cosmetics industries. The commercial large-scale production of these chemicals relies on traditional homogeneous catalysis processes making use of strong mineral acids or alkalis. This technology possesses severe drawbacks, related to the generation of large amounts of by-products, high energy demand, and heterogeneity of the ester mixtures obtained. The development of new processes based on more selective solid catalysts has, therefore, a great economical interest. This contribution reviews the scientific and technical literature in this field. It is proposed that solid catalysts based on MCM-41 and other mesostructures could give rise to the development of new, more efficient processes for the large-scale synthesis of fatty acid esters of polyols. [ABSTRACT FROM AUTHOR]

Abstract: A procedure to enable the use of the very open framework Zn-STA-1 as catalyst, based on in situ calcination in a water-free environment, has been developed. The material shows a remarkable performance in the m-xylene isomerization test reaction, comparable to that of USY zeolite. The reported experimental procedure avoids the collapse of the SAO structure upon calcination, which has prevented the use of this very open framework structure in catalytic applications, and provides a promising new microporous catalyst for processing bulky molecules. [Copyright &y& Elsevier]

In this work, a systematic study of the acid extraction of the surfactant present in MCM-41 mesoporous materials was carried out. Two organic solvent/acid mixtures were used at various temperatures and for different periods of time. Propylthiol groups were subsequently grafted onto the surface by reacting the mesoporous silica with 3-mercaptopropyltrimethoxysilane. The resulting organic matter loading is compared with the one yielded by grafting of calcined samples. Acid catalysts were obtained by oxidation of the ㅡSH groups to the ㅡSO3H form. The catalysts were tested for alkylation of benzene with 1-dodecene. These materials were characterized by means of XRD, themogravimetric analysis, N2 adsorption–desorption isotherms, organic elemental analysis and acid titration. The acid extraction of the surfactant allowed the preparation of catalysts with a high concentration of active centers. [Copyright &y& Elsevier]

[Display omitted] • Avelino Corma's group at the Instituto de Catálisis y Peroleoquímica, the seed of the Instituto de Tecnología Química (ITQ). • The beginnings of ITQ in Valencia, creating a way of doing science. • From the laboratory to the industry, some ITQ success stories. • Basic science applied to solve real industrial problems, one of the founding pillars of ITQ. • The ITQ, a multidisciplinary approach to research in the field of zeolites. [ABSTRACT FROM AUTHOR]

Highlights: [•] TAPO-5 improves its activity in cyclohexene oxidation under anhydrous conditions. [•] Reaction mixture can become almost anhydrous by Soxhlet extraction. [•] TAPO-5 promotes the formation of products through allylic mechanism. [•] Ti(III)APO-5 is more active and selective to allylic products than Ti(IV)APO-5. [Copyright &y& Elsevier]