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Thermal decomposition of aluminum isopropoxide (AIP) in inert organic solvents (toluene and mineral oil) resulted in the formation of χ-alumina. Phase evolution by calcination at various temperatures for this alumina was studied via X-ray diffraction. The results suggest a direct transformation from χ-alumina to α-alumina at approximately 1180°C, without the formation of κ-alumina phase, while still maintaining the small particle size (

Zirconia has been shown to be effective both as a catalyst and a support [1]. It has been found that zirconia has high catalytic activities for isomerization of olefins [2] and epoxides [3]. Zirconia is an important promoter in the catalytic converter system for automobile control and has been shown to help regulate the redox reaction of the ceria catalyst support. Several methods have been developed to increase the surface area and stabilize the tetragonal phase of zirconia. These include the addition of many different additives such as sulfate [4], potassium [5, 6], or rare earth ions [7–13]. It has been reported that the surface area of zirconia is enlarged by the presence of a small amount of silica in the sol-gel process [14, 15]. However the effect of these additives varied by the preparation method and the amount of additives. Inoue et al. have developed a processing method for zirconia that involve the thermal decomposition of zirconium alkoxides in organic solvents. Large surface area zirconia can be obtained directly without bothersome procedures such as purification of the reactants or handling in inert atmosphere [13, 16]. In this paper, we prepare silica-modified zirconia with high surface area and high thermal stability by the glycothermal method. Zirconium n-propoxide 15 g and an amount of tetraethyl orthosilicate at Si/Zr ratio of 0–0.15 were suspended in 130 ml of 1,4-butanediol and then this mixture was placed in a 300 ml autoclave. The autoclave was purged with nitrogen, and the mixture was heated to 300 ◦C and kept at 300 ◦C for 2 h. After the autoclave was cooled, the obtained product was repeatedly washed with methanol, collected by centrifugation and air-dried. The calcination of the product was carried out in a box furnace for 1 h. Powder X-ray diffraction (XRD) patterns were collected on a Siemens XRD D5000 using Cu Kα radiation and a carbonmonochromator. The crystallite size was calculated by the Scherrer equation from the half-height width of 202 diffraction peak. Scanning electron microscopy mea

In order to concentrate and separate CO2 from N2-diluted gaseous mixture, the adsorption characteristics and separation performance of various kinds of microporous crystals to be used as adsorbents were investigated. Eight-oxygen-member-ring microporous crystals like zeolite ZSM-34 and silicoaluminophosphate SAPO-34 adsorbed large quantities of CO2 and N2. Metal incorporation in those crystals improved their performance. For ZSM-34 it significantly increased specific surface area and amounts of adsorption, and for SAPO-34 it increased the effective diffusivity to some extent. For Ni-SAPO-34, 2.9% CO2 diluted with N2 could be concentrated to 62.9% and 84.4% at the CO2 recoveries of 33.0% and 20.6%, respectively, by using a pressure swing adsorption (PSA) technique in the pressure range between 10 and 2 kg cm−2 (gauge) and at −75°C.

The performance of various metal ion-exchanged A-type zeolites and metal-incorporated A-type zeolites for O 2 and N 2 adsorption was studied to provide a pressure swing adsorption (PSA) process. Metal-incorporated A-type zeolites adsorbed N 2 in larger quantities than metal ion-exchanged A-type zeolites. Compared with Na-A zeolite, both Cu-incorporated and Ni-incorporated A-type zeolites adsorbed larger quantities of N 2 . The incorporation of Cu or Ni enlarged the pore size of the zeolite, while Fe incorporation reduced it. However, the adsorption volume ratio of O 2 to N 2 could be increased to as high as 4.2 on Fe-incorporated A-type zeolite calcined at 750°C, which was the highest value among the samples tested. The amount of adsorption of O 2 was 38.0 ml g −1 , which was comparable with ordinary Na-A zeolite. The Fe incorporation markedly improved the performance of ordinary Na-A zeolite in O 2 /N 2 separation. Therefore, Fe-incorporated A-type zeolite has a high potential as a good adsorbent for pressure swing adsorption in O 2 /N 2 separation from air.

Rapid catalytic reaction for methane reforming with CO2 and H2O was realized using a Ni-based composite catalyst consisted of Ni-CeC-2-Pt and Rh-modified one. Syngas and CO 2 -H 2 mixture were selectively converted into gasoline and light olefins via methanol using seriesly connected 2nd-stage reactors. In the 1st-stage reactor, newly developed highly active methanol synthesis catalysts were packed, and in the 2nd-stage reactor, microporous crystalline catalysts, i.e., H-Fe-silicate and SAPO-34 were packed, respectively for synthesis of gasoline and olefins.

Development in highly active catalysts for steam reforming of methane and partial oxidation of methane was conducted to produce hydrogen with high rates. A Ni-based three—component catalyst such as Ni-La 2 0 3 —Ru was very suitable for both reactions. The catalyst composition was set at 10 wt% Ni, 5.6 wt% La 2 0 3 , and 0.57 wt% Ru; or molar ratios of these components were 1: 0.2 : 0.03. Even such a low concentration, the precious metal enhanced the reaction rate very markedly, and this synergistic effect was ascribed to the hydrogen spillover effect through the part of precious metal and it brought about a more reduced surface of main catalyst component.