The presence of basic centers in some oxides has been recognized for a long time as being important in catalysis [1-4]. Usually both basic and acid sites exist simultaneously. The two centers may work independently or in a concerted way. For instance, in alcohol transformation, dehydration is favored on acidic sites and dehydrogenation on basic centers [3,5]. A large variety of materials are cited as having basic character. They include single-metal oxides (MgO, CaO, ZnO), supported alkali metals (Na/MgO, K/K2CO3), mixed-metal oxides (MgO-A12O3, ZnO-SiO2, MgO-TiO2), zeolites (X and Y saturated with alkaline cations of low electronegativity), hydrotalcite-type anionic clays, asbestoslike materials, carbon-supported basic catalysts, and basic organic resins. ∗ Present address: 16 rue Francois Gillet, 69003 Lyon, France.

Basic zeolites : Characterization and uses in adsorption and catalysis

Alternative energy technologies are greatly hindered by significant limitations in materials science. From low activity to poor stability, and from mineral scarcity to high cost, the current materials are not able to cope with the significant challenges of clean energy technologies. However, recent advances in the preparation of nanomaterials, porous solids, and nanostructured solids are providing hope in the race for a better, cleaner energy production. The present contribution critically reviews the development and role of mesoporosity in a wide range of technologies, as this provides for critical improvements in accessibility, the dispersion of the active phase and a higher surface area. Relevant examples of the development of mesoporosity by a wide range of techniques are provided, including the preparation of hierarchical structures with pore systems in different scale ranges. Mesoporosity plays a significant role in catalysis, especially in the most challenging processes where bulky molecules, like those obtained from biomass or highly unreactive species, such as CO2 should be transformed into most valuable products. Furthermore, mesoporous materials also play a significant role as electrodes in fuel and solar cells and in thermoelectric devices, technologies which are benefiting from improved accessibility and a better dispersion of materials with controlled porosity.

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Mesoporous materials for clean energy technologies

Influence of preparation method on the performance of Zn-containing HZSM-5 catalysts in methanol-to-aromatics

A methanol to olefins review: Diffusion, coke formation and deactivation on SAPO type catalysts

Structure–deactivation relationship for ZSM-5 catalysts governed by framework defects

Correlation between the crystal zize and catalytic properties of ZSM-5 zeolites

A catalyst for production of aromatic hydrocarbons and a process for producing aromatic hydrocarbons from various hydrocarbons using said catalyst are disclosed. The catalyst comprises a L-type zeolite treated with a halogen-containing compound and platinum deposited thereon, which is of high activity and has a long service life. The process of the present invention using the catalyst enables to produce aromatic hydrocarbons in a yield as high as not less than 80% for a long time. The hydrocarbon feedstock is selected from paraffin, olefin, acetylene, cyclic paraffin, and cyclic olefin-based hydrocarbons.

Catalyst for the production of aromatic hydrocarbons and process for the production of aromatic hydrocarbons using said catalyst

We found that the treatment of L zeolite with monochlorotrifluoromethane (CF3Cl) increased the catalytic activity for n-hexane aromatization. To clarify the effects of halogen atoms on the electronic state of platinum particles on the CF3Cl-treated L zeolite, we used infrared spectroscopy of adsorbed CO, X-ray photoelectron spectroscopy (XPS ), X-ray absorption near-edge structure (XANES ) and X-ray absorption fine structure (EXAFS). The shifts of the CO absorption band and Pt 4f7/2 binding energy to lower wavenumber and binding energy, respectively, suggest that the platinum particles are electron-rich compared with those on the untreated L zeolite. From the results of XANES and EXAFS, this is attributed to their poorer interaction with oxygen atoms of the L zeolite support. It is thought that halogen atoms on the Pt/FKL play an important role in preventing interaction between the platinum particles and the oxygen atoms of the L zeolite support.

Electronic state of platinum supported on the monochlorotrifluoromethane-treated alkaline L zeolite

A catalyst for production of aromatic hydrocarbons and a process for producing aromatic hydrocarbons from various hydrocarbons using said catalyst are disclosed. The catalyst comprises a L-type zeolite treated with a halogen-containing compound and platinum deposited thereon, which is of high activity and then has a long service life. The process of the present invention using the catalyst enables to produce aromatic hydrocarbons in a yield as high as not less than 80% for a long time. The hydrocarbon feedstock is selected from paraffin, olefin, acetylene, cyclic paraffin, and cyclic olefin-based hydrocarbons.

Catalyst for the production of aromatic hydrocarbons

There are disclosed a catalyst obtainable by the simple manufacturing process, having a high and persistent catalytic activity for a long-term production of aromatic hydrocarbon and a process for efficiently producing aromatic hydrocarbons from nonaromatic hydrocarbon by the use of the catalyst. The catalyst comprises L-type zeolite with both platinum components and halogen components simultaneously supported thereon, and is capable of producing aromatic hydrocarbons over a long-term stable operation with a high yield and high activity.

Hisashi Katsuno

Papers

Correlation between the crystal zize and catalytic properties of ZSM-5 zeolites

Catalyst for the production of aromatic hydrocarbons and process for the production of aromatic hydrocarbons using said catalyst

Electronic state of platinum supported on the monochlorotrifluoromethane-treated alkaline L zeolite

Catalyst for the production of aromatic hydrocarbons

Catalyst for the production of aromatic hydrocarbons and process for producing aromatic hydrocarbons by the use thereof