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Pt/La1−xBixOF/SBA-16 (SBA-16: Santa Barbara Amorphous no. 16) catalysts were prepared to produce dihydroxyacetone (DHA) from glycerol under moderate conditions. By using 7 wt% Pt/16 wt% La0.95Bi0.05OF/SBA-16, the DHA yield reached up to 78.4% (glycerol conversion: 100%) after reacting for 6 h at 30 °C in an atmospheric open-air system. [ABSTRACT FROM AUTHOR]

Novel catalysts of Pt/La1−xBixOF/SBA‐16 (SBA‐16: Santa Barbara Amorphous No. 16) were synthesized, and their catalytic activities for phenol decomposition in the liquid phase were investigated. Lanthanum oxyfluoride (LaOF) was selected as the promoter due to its contribution to the smooth migration of oxygen species in the lattice and the acceleration of phenol adsorption on the catalyst surface. Reducible Bi3+ ions were introduced in the LaOF lattice to provide oxygen supply ability to LaOF. Among the prepared catalysts, the highest activity was obtained for the 7 wt% Pt/16 wt% La0.99Bi0.01OF/SBA‐16 catalyst, which could remove 97% of phenol after 5 h of reaction at 80°C in an open‐air atmosphere. [ABSTRACT FROM AUTHOR]

Effective glyceric acid production from glycerol was demonstrated under mild conditions in an open-air system at room temperature in the absence of base or oxygen gas flow by employing a Pt/CeO2–ZrO2–Fe2O3/Santa Barbara Amorphous No. 16 (SBA-16) catalyst. At a low loading amount of CeO2–ZrO2–Fe2O3 (16 wt%Ce0.64Zr0.16Fe0.20O2−δ/SBA-16), the oxygen release and storage abilities and high acidity of the catalyst afforded a high glyceraldehyde yield, owing to the enhancement of the oxidation ability of the Pt activator and the acceleration of the desorption of glyceraldehyde. The increase in CeO2–ZrO2–Fe2O3 loading amount further improved the oxygen release and storage abilities and lowered the catalyst acidity induced by crystallite growth and particle aggregation. The high oxygen release and storage abilities, as well as the low acidity, contributed to the high glyceric acid yield; the highest activity for glyceric acid production was obtained for the 7 wt%Pt/40 wt%Ce0.64Zr0.16Fe0.20O2−δ/SBA-16 catalyst. The glyceric acid yield increased up to 68.2% after 10 h of reaction in atmospheric air at 30°C. [ABSTRACT FROM AUTHOR]

The effects of the Bi3+ introduction and the oxygen release and storage abilities on selective oxidation of glycerol into dihydroxyacetone (DHA) were demonstrated using Pt/CeO2-ZrO2-Bi2O3-SnO2/SBA-16 (SBA-16: Santa Barbara Amorphous No. 16) catalysts. By introducing Bi3+ or Sn4+/2+ ions into the CeO2-ZrO2 promoter, the oxygen release and storage abilities were enhanced, which led to increased glycerol conversion. The improvement in the DHA yield was affected by the introduction of Bi3+, which might accelerate selective oxidation of a secondary hydroxy group in glycerol caused by the geometric effect. The highest activity was obtained for Pt/Ce0.64Zr0.16Bi0.15Sn0.05O2−δ/SBA-16, which showed high oxygen release and storage abilities and a high number of Bi3+ ions, with the DHA yield increasing to 53% and high rates of glycerol conversion (74%) and DHA selectivity (72%) after reaction at a moderate temperature of 30 °C for 4 h in atmospheric air. [ABSTRACT FROM AUTHOR]

A Pt/CeO2-ZrO2-Bi2O3/SBA-16 catalyst was prepared to realize highly selective oxidation of glycerol to produce dihydroxyacetone (DHA). An active oxygen supply from the CeO2-ZrO2-Bi2O3 promoter effectively oxidized glycerol to produce DHA under moderate conditions (i.e. at 30°C without applied pressure). After a 4 h catalytic reaction using the Pt/CeO2-ZrO2-Bi2O3/SBA-16 catalyst, the DHA yield and selectivity rose to 76% and 84%, respectively. [ABSTRACT FROM AUTHOR]

A Pt/CeO2-ZrO2-SnO2/SBA-16 (SBA-16: Santa Barbara Amorphous No. 16) catalyst was developed for the efficient removal of 1,4-dioxane. Because the catalyst showed synergistic action between the high catalytic activity of Pt and the high oxygen release and storage abilities of CeO2-ZrO2-SnO2, high catalytic efficiency in the liquid phase was obtained in an air atmosphere without the supply of any strongly oxidizing additives or photoirradiation. After reaction at 80°C for 4 h, the residual percentage of 1,4-dioxane reached 31%. Furthermore, the Pt/CeO2-ZrO2-SnO2/SBA-16 catalyst exhibited high reusability and durability and the rate of net decrease in 1,4-dioxane reached 44% at 80°C. [ABSTRACT FROM AUTHOR]

PdO/CeO2-ZrO2-NiO/γ-Al2O3 catalysts were prepared for the combustion of methane at moderate temperatures. The introduction of a small amount of NiO within the cubic fluorite CeO2-ZrO2 structure as a promoter effectively enhanced the oxygen release and storage abilities of the catalysts, thereby achieving the complete oxidation of methane. The catalyst with the highest activity for methane combustion was 11.3 mass% PdO/20 mass% Ce0.64Zr0.16Ni0.2O1.9/γ-Al2O3, and efficient combustion was realized at a temperature as low as 300 °C. [ABSTRACT FROM AUTHOR]

Pt/CeO2-ZrO2-Bi2O3-PbO/SBA-16 (SBA-16: Santa Barbara Amorphous No. 16) catalysts were synthesized to produce hydroxypyruvic acid by glycerol oxidation. In the catalysts, the introduction of PbO into CeO2-ZrO2-Bi2O3 improved the oxygen release and storage abilities owing to the synergistic redox reaction of Pb2+/4+ and Ce3+/4+, which facilitated the oxidation ability of Pt. In addition, the oxidation of the secondary OH group in glycerol might be accelerated by the geometric effects of glycerol, Pt, and Bi3+ or Pb2+/4+. Furthermore, the moderate reaction conditions such as room temperature and open-air atmosphere enabled the suppression of further oxidation of hydroxypyruvic acid. The highest catalytic activity was obtained for 7 wt% Pt/16 wt% Ce0.60Zr0.15Bi0.20Pb0.05O2−δ/SBA-16, which provided a hydroxypyruvic acid yield maximum of 24.6%, after the reaction for 6 h at 30 °C in atmospheric air. [ABSTRACT FROM AUTHOR]

Catalytic combustion of methane was investigated on Pt and PdO-supported CeO-ZrO-BiO/γ-AlO catalysts prepared by a wet impregnation method in the presence of polyvinylpyrrolidone. The catalysts were characterized by X-ray fluorescence analysis, X-ray powder diffraction, X-ray photoelectron spectra, transmission electron microscopy, and BET specific surface area measurements. The Pt/CeO-ZrO-BiO/γ-AlO and PdO/CeO-ZrO-BiO/γ-AlO catalysts were selective for the total oxidation of methane into carbon dioxide and steam, and no by-products such as HCHO, CO, and H were obtained. The catalytic activities of the PdO/CeO-ZrO-BiO/γ-AlO catalysts were relatively higher than those of the Pt-supported catalysts, due to the facile re-oxidation of metallic Pd into PdO based on lattice oxygen supplied from the CeO-ZrO-BiO bulk. A decrease in the calcination temperature during the preparation process was found to be effective in enhancing the specific surface area of the catalysts, whereby particle agglomeration was inhibited. Optimization of the PdO amount and calcination temperature enabled complete oxidation of methane at temperatures as low as 320 °C on the 11.6 wt% PdO/CeO-ZrO-BiO/γ-AlO catalyst prepared at 400 °C. [ABSTRACT FROM AUTHOR]

A novel Pt/CeO2–ZrO2–Bi2O3catalyst was prepared to realize complete CO oxidation at room temperature or below even in the presence of moisture. Using this catalyst, a high CO oxidation activity and a high stability against moisture have been realized simultaneously. [ABSTRACT FROM AUTHOR]

A Pt/Ce0:64Zr0:16Bi0:20O1:90/γ-Al2O3 catalyst was prepared in order to establish complete oxidation of ethylene at temperatures below 100°C. Ethylene was completely oxidized over the catalyst as low as at 65°C, while over Pt/γ-Al2O3, which has been well known as an active oxidation catalyst, complete oxidation was achieved at 145°C. [ABSTRACT FROM AUTHOR]

Excellent oxidation catalysts, which can completely oxidize volatile organic compounds (VOCs) and methane at moderate temperatures, have been prepared. A new concept based on the design of solid electrolytes has been applied to the preparation of the catalysts. By the synergetic effect of precious metals and rare earth oxides, complete oxidation of VOCs and methane into CO2 and steam at moderate temperatures has been realized for the present catalysts. [ABSTRACT FROM AUTHOR]

• Novel Pt/La 1− x Ni x O 1− x /2 F/γ-Al 2 O 3 catalysts were developed for toluene combustion. • Ni-doped LaOF showed the oxygen release and storage abilities. • Highly toluene combustion activity was obtained for Pt/La 0.95 Ni 0.05 O 0.975 F/γ-Al 2 O 3. Novel Pt/La 1− x Ni x O 1− x /2 F/γ-Al 2 O 3 catalysts were developed for toluene combustion by using Ni-doped LaOF as promoters. We selected the LaOF solid well-known as the oxide ion conducting solid electrolyte in order to migrate active oxygen smoothly to the platinum activator, and introduced Ni2+/3+ ions into the LaOF lattice to provide the redox property. Among the samples prepared, the Pt/La 0.95 Ni 0.05 O 0.975 F/γ-Al 2 O 3 catalyst exhibited the highest catalytic activity, and toluene was completely oxidized at 120 °C. [ABSTRACT FROM AUTHOR]