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Supported nickel catalysts with a core/shell structure of Ni/Al 2 O 3 and Ni/MgO–Al 2 O 3 synthesized under multi-bubble sonoluminescence (MBSL) conditions were tested for mixed steam and dry (CO 2 ) reforming and autothermal reforming of methane. In the previous tests, the supported Ni catalysts made of 10% Ni loading on Al 2 O 3 or MgO–Al 2 O 3 had shown good performances in the steam reforming of methane (methane conversion of 97% at 750 °C), in the partial oxidation of methane (methane conversion of 96% at 800 °C) and in dry reforming of methane (methane conversion of 96% at 850 °C) and showed high thermal stability for the first 50–150 h. In this study, the supported Ni catalysts showed good performance in the mixed and autothermal reforming of methane with their excellent thermal stability for the first 50 h. In addition, very interestingly, there was no appreciable carbon deposition on the surface of the tested catalysts after the reforming reaction.

Supported nickel catalysts with core/shell structures of Ni/Al 2 O 3 and Ni/MgO–Al 2 O 3 were synthesized under multi-bubble sonoluminescence (MBSL) conditions and tested for dry reforming of methane (DRM) to produce hydrogen and carbon monoxide. A supported Ni catalyst made of 10% Ni loading on Al 2 O 3 and MgO–Al 2 O 3 , which performed best in the steam reforming of methane (97% methane conversion at 750 °C) and in the partial oxidation of methane (96% methane conversion at 800 °C), showed also good performance in DRM and excellent thermal stability for the first 150 h. The supported Ni catalysts Ni/Al 2 O 3 and Ni/MgO–Al 2 O 3 yielded methane conversions of 92% and 92.5%, respectively and CO 2 conversions of 95.0% and 91.8%, respectively, at a reaction temperature of 800 °C with a molar ratio of CH 4 /CO 2 = 1. Those were near thermodynamic equilibrium values.

Lanthanide sulfates, Hydrothermal synthesis, Three-dimensional structuresTwo- or three-dimensional framework materials containing rich structural diversities are of continuous interest attributable to their technologically important properties and potential appli-cations such as catalysis, ion-exchange, adsorption, intercala-tion, and radioactive waste remediation.

The catalytic performance of transition metal (Fe2+ or Cu2+) containing nano-sized hol low core mesoporous shell carbon (HCMSC) heterogeneous catalysts for the hydroxylation of phenol with hydrogen peroxide (H2O2) in water was investigated in a batch reactor. The metal-containing HCMSC catalyst showed higher activity than the same metal ion-exchanged zeolites. The nature of the metal and its content in the HCMSC had remarkable influence on the reaction results under the typical reaction conditions (PhOH/H2O2=3, reaction temperature=60 ‡C). Fe2+ containing HCMSC catalyst showed high catalytic activity with phenol conversion of 29%, selectivity to catechol (CAT) and hydroquinone (HQ) about 85%, H2O2 effective conversion about 70% and selectivity to benzoquinone (BQ) below 1% in the batch system.

Copper complexes have been directly incorporated into cellulose acetate (CA) and the resulting light blue colored homogeneous films of 5-20 wt.% copper acetate complex concentrations are found to be thermally stable up to200 °C. The reaction chemistry of Cu in CA has been investigated by reacting them with small gas molecules such as CO, H 2 , D 2 , O 2 , NO, and olefins in the temperature range of 25-160 °C, and various Cu-hydride, -carbonyl, -nitrosyl, and olefin species coordinated to Cu sites in CA are characterized by IR and UV/ Vis spectroscopic study. The reduction of Cu(II) complexes by reacting with H 2 gas at the described conditions results in the formation of Cu 2 O and copper metal nanoparticles in CA, and their sizes in 30-120 nm range are found to be controlled by adjusting metal complex concentration in CA and/or the reduction reaction conditions. These small copper metal particles show various catalytic reactivity in hydrogenation of olefins and CH 3 CN; CO oxidation; and NO reduction reactions under relatively mild conditions.

Palladium acetate complexes have been incorporated into polycarbonate (PC) films as a dispersion medium using tetrahydrofuran (THF). The resulting light brown-coloured homogeneous films of 10–30 wt.% Pd metal complex concentration are found to be thermally stable up to 150°C, and the relatively electron rich oxygen atoms of ketone groups in polycarbonate molecules are assumed to interact with Pd complexes on the basis of their infrared spectroscopic and thermal analyses. The reaction chemistry of Pd in PC has been investigated by reacting Pd sites with small gaseous molecules such as CO, H 2 , O 2 , NO, and olefins in the temperature range of 25 to 150°C, and various Pd-carbonyls, -hydride, -nitrosyl, and -ethylene species formed in PC are characterized. The treatment of Pd-containing PC film with H 2 gas at 120°C produces small Pd metal particles of ca. 40–330 A in diameter in PC, which show various catalytic reactivities in CO oxidation, NO reduction, dimethyl carbonate formation and hydrogenation of styrene-monomer.

RhCl[P(C 6 H 5 ) 3 ] 3 complexes have been incorporated in polycarbonate (PC) as a dispersion medium using cosolvent (THF). The interactions between Rh(I) complexes and polycarbonate polymer molecules are studied by infrared spectroscopy and thermal analysis. The reaction chemistry of Rh in PC films has been investigated by reacting Rh sites in PC with small gaseous molecules like CO, H 2 , D 2 , O 2 , NO, C 2 H 2 , and C 2 H 4 in the temperature range 25∼150°C. Various Rh–carbonyls, –hydride, –nitrosyl, and –superoxo dioxygen species formed in PC films are characterized by infrared spectroscopy. The Rh complexes in PC are easily reduced by reacting them with H 2 gas and such reduction results in the formation of small Rh metal particles of 20∼30 A in diameter in PC. The Rh complexes in PC show interesting catalytic reactivities such as hydrogenation of olefin and acetylene, oxidation of CO, reduction of NO, methanol synthesis from CO or CO 2, and oxidation of alcohol under relatively mild conditions.

RuCl3·3H2O complexes have been incorporated into polycarbonate using solvent. The interactions between Ru complexes and polycarbonate (PC) are examined by infrared spectroscopy and thermal analysis. The reaction chemistries of these Ru-containing films have been investigated by reacting the Ru sites with CO, O2, H2, D2, NO, and C2H4. They show interesting catalytic activities in various gas phase reactions under relatively mild conditions such as NO reduction, hydrogenation of ethylene and benzene, water-gas shift reaction, and oxidation of n-butyl sulfide.

Palladium (Pd) acetate complexes have been incorporated in polysulfone (PS) as a dispersion medium using cosolvent (tetrahydrofuran). The resulting brown-colored [PS-Pd] films of 10–40 wt% complex concentration are thermally stable up to 140°C. Upon incorporation of Pd metal into PS, the glass transition temperatures of the films increase as Pd metal concentration increases. The acetate ligands in [PS-Pd] films are found to be substituted by Cl−1 or CN−1 ligands in aqueous solution. As a result of the relatively easy reduction of Pd(II) in PS to Pd(0), palladium metal particles in various sizes are observed to be formed in PS. The Pd complexes in PS show catalytic activities in hydrogenation of ethylene, CO oxidation and NO reduction by CO or H2 gases under relatively mild conditions.

RuCl 3 · 3H 2 O complexes are incorporated into polysulfone (PS) as a dispersion medium using a cosolvent (tetrahydrofuran) in the metal complex concentration range of 5–30 wt.%. The interactions between Ru(III) complexes and PS are examined by infrared spectroscopy and thermal analyses (differential scanning calorimetry, DSC). The chemical reactivities of Ru in PS are investigated by reacting Ru sites with CO, H 2 , O 2 , NO, D 2 , N 2 , and C 2 H 4 gases in the static state under relatively mild conditions. Various Ru carbonyl, nitrosyl and hydride species formed in PS are characterized by infrared spectroscopic analyses and isotopic methods. Partial reduction of Ru(III) to Ru(II) is observed in reactions of the Ru-containing PS films with CO-H 2 O or H 2 . These films show catalytic activities in the hydrogenation of ethylene, a water-gas shift reaction and reduction of NO under relatively mild conditions.

RuCl3·3H2O complexes have been incorporated in cellulose acetate (CA) as a dispersion medium using a cosolvent (tetrahydrofuran). The interactions between Ru(III) complexes and CA were examined by infrared spectroscopy and thermal analysis (DSC). The reaction chemistry of 10 wt.% ruthenium-containing CA films was investigated by reacting Ru sites with CO, H2, O2 and H2O under mild conditions. Four different Ru-carbonyls formed in CA were characterized; among them, physically adsorbed CO molecules on Ru sites in CA were found to be relatively reactive. Treatment of the Ru-containing CA films with hydrogen (600 torr) at 130 °C produced quite stable ruthenium hydride species, which was confirmed by identifying the corresponding ruthenium deuteride. Partial reduction of RU(III) to RU(II) was observed in reactions of the films with CO/H2O or H2. The Ru-containing CA films show catalytic activities in oxidation of CO to CO2 and the water-gas shift reaction under relatively mild conditions.

RhCl [P(C6H5)3]3 complexes have been incorporated in cellulose acetate as a dispersion medium using cosolvent (tetrahydrofuran). The interactions between Rh (I) complexes and cellulose acetate (CA) are examined by infrared spectroscopy and thermal analysis. The chemical reactivities of Rh–CA films have been investigated by reacting Rh sites with CO, H2, O2, and C2H4 in the temperature range 90–150°C and at a pressure of less than 1 atm. Three different Rh-carbonyls and a Rh-hydride species formed in CA are characterized by their infrared spectra. Treatment of 10 or 20 wt % Rh–CA films with hydrogen (600 torr) at 150°C produces small Rh metal particles of ca. 10 A or less in diameter in CA, which show catalytic activities under mild conditions in various reactions such as hydrogenation of C2H4, oxidation of CO, and Fischer–Tropsch type reactions.

Ru(III) ions have been incorporated in the domains of sulfonated linear polystyrene (PSSA) as a dispersion medium to form PSSA-Ru(III) films through an ion-exchange process. The chemical reactivities of PSSA-Ru(III) films have been investigated by reacting the ruthenium sites with CO, H2, O2, CH3OH, and C2H5OH under mud conditions. The reactions of PSSA-Ru(III) films with CO (400 Torr) in the temperature range 25–186 °C resulted in four different Ru carbonyl species, which were characterized by their infrared spectra. Treatment of PSSA-Ru(III) films with hydrogen (400 Torr) at 150 °C produced ruthenium hydride species, which were confirmed by identifying the corresponding ruthenium deutendes. Also, HD exchange on benzene rings of the polystyrene backbone was found to occur during the reaction of PSSA-Ru(III) films with D2. The reactions of aqueous methanol and ethanol with PSSA-Ru(III) films produced ruthenium carbonyl species, but there was no evidence of the formation of ruthenium hydride or ruthenium formyl groups in the infrared spectra. Static Fischer-Tropsch type reactions of PSSA-Ru(III) powder with CO (300 Torr) and H2 (300 Torr) at 150 °C showed the formation of various aliphatic hydrocarbons, oxygen-containing hydrocarbon compounds, and CO2 in the mass and infrared spectra.