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941.
Yongwon Seo Sung-Ho Jo Ho-Jung Ryu Hee Dal Bae Chong Kul Ryu Chang-Keun Yi 《Korean Journal of Chemical Engineering》2007,24(3):457-460
A bubbling fluidized bed reactor was used to study CO2 capture from flue gas by using a potassium-based solid sorbent, sorbKX35 which was manufactured by the Korea Electric Power
Research Institute. A dry sorbent, sorbKX35, consists of K2CO3 for absorption and supporters for mechanical strength. To increase initial CO2 removal, some amount of H2O was absorbed in the sorbent before injecting simulated flue gas. It was possible to achieve 100% CO2 removal for more than 10 minutes at 60°C and a residence time of 2 s with H2O pretreatment. When H2O pretreatment time was long enough to convert K2CO3 of sorbKX35 into K2CO3 · 1.5H2O, CO2 removal was excellent. The results obtained in this study can be used as basic data for designing and operating a large scale
CO2 capture process with two fluidized bed reactors.
This work was presented at the 6
th
Korea-China Workshop on Clean Energy Technology held at Busan, Korea, July 4–7, 2006. 相似文献
942.
Hongcang Zhou Baosheng Jin Zhaoping Zhong Yaji Huang Rui Xiao Youfei Zheng 《Korean Journal of Chemical Engineering》2007,24(3):489-494
The coal partial gasification catalyzed by limestone, sodium carbonate and dolomite was studied using a bench-scale atmospheric
fluidized bed in the presence of air and steam at 900 °C. The effects of limestone, sodium carbonate and dolomite on composition,
heating value, gas yield of product gas and carbon conversion in the catalytic coal partial gasification have been examined.
The experimental results show that the catalysts can effectively improve the gas quality, the heating value and the gas yield
of product gas and carbon conversion. The catalytic effect of sodium carbonate is better than that of limestone and dolomite.
The increase of limestone loading can enhance the quality of product gas, such as the content of combustible gas, the high
heating value and the gas yield, during coal partial gasification.
This work was presented at the 6
th
Korea-China Workshop on Clean Energy Technology held at Busan, Korea, July 4–7, 2006. 相似文献
943.
Thomas Bürgi Fachri Atamny Axel Knop‐Gericke Michael Hävecker Thomas Schedel‐Niedrig Robert Schlögl Alfons Baiker 《Catalysis Letters》2000,66(3):109-112
The adsorption of ethyl pyruvate on Pt(111) has been studied by in situ XANES measurements in the presence and absence of
hydrogen. Depending on the hydrogen and ethyl pyruvate pressure, the C and O K‐edge spectra exhibit distinctly different angular
dependence. Without hydrogen ethyl pyruvate is oriented preferentially perpendicular to the surface, indicating bonding via
the O lone pairs. In the presence of hydrogen the mean orientation is more tilted towards the surface. Likely, ethyl pyruvate
also interacts with Pt via its π system under these conditions. The observed angle‐dependent shift of the energy of the π*
and σ* resonances indicates the coexistence of differently adsorbed ethyl pyruvate species. The experimental findings demonstrate
the importance of the in situ approach for unraveling the adsorption mode of ethyl pyruvate in the enantioselective hydrogenation
over cinchona‐alkaloid‐modified Pt.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
944.
Bin Li Chang-Rui Zhang Si-Qing Wang Feng Cao Yong-Gang Jiang 《Refractories and Industrial Ceramics》2007,48(4):280-283
A new wave-transparent composite reinforced by silica fibers with a hybrid matrix comprising BN and Si3N4 was prepared by precursor infiltration and pyrolysis, and it was heat-treated at elevated temperatures. The variations of
the composite during heat treatments were characterized and investigated by Fourier transform infrared spectroscopy (FT-IR),
X-ray diffraction (XRD) and scanning electron microscopy (SEM). The as-received composite exhibits good mechanical properties,
and it is almost amorphous. When treated at 1600°C, it turned brittle, and silica fibers in it were fused; the composite showed
a good crystalline form. When treated at 2100°C, the composite broke into pieces, and the composition showed only BN. Si3N4 was decomposed, and silica fibers were volatilized. The presence of BN probably affected the phase transitions of silica
fibers.
__________
Translated from Novye Ogneupory, No. 8, pp. 49–52, August 2007. 相似文献
945.
The hydrodynamic and gas mixing characteristics have been determined in a FCC regenerator (0.48 m I.D.x3.4 m high) with FCC
particles. Solids holdup in the dense bed decreases with increasing gas velocity, but it increases in the freeboard region.
The bubble/void fraction increases with an increase along the bed height at a given gas velocity and increases with increasing
gas velocity at a constant bed height. Backmixed tracer gas at the wall region is higher than that at the center region of
the bed. The gas backmixing coefficient decreases with increasing gas velocity. 相似文献
946.
TiO2 was sintered in HCl atmospheres to enhance the effects of vapor transport. Little or no densification is observed for temperatures between 1000° and 1300°C. Particle coarsening occurs at temperatures above 1200°C. The apparent activation energy for particle growth is 114 kJ/mol. It is concluded that the primary mass-transport mechanism is vapor transport while the particle growth rate is limited by grain-boundary mobility . 相似文献
947.
Karl D. Hammond Geoffrey A. Tompsett Scott M. Auerbach W. Curtis Conner 《Journal of Porous Materials》2007,14(4):409-416
We present a non-destructive, reusable apparatus with which to measure physical adsorption isotherms of intact porous membranes.
We developed a two-piece sample container to make reliable sorption measurements of porous membranes, the properties of which
may differ from those of powders due to crystal intergrowth. This novel system employs a resealable container that can be
immersed in a cryogenic bath, into which tubular, planar, or other porous membranes and films may be placed. Detailed sorption
isotherms, including high-resolution adsorption in the low pressure (micropore-filling) region, are shown for MFI-type zeolite
membranes grown on two types and configurations of α-alumina support. 相似文献
948.
Michael K. Cinibulk John R. Welch Randall S. Hay 《Journal of the American Ceramic Society》1996,79(9):2481-2484
A method of preparing transmission electron microscopy (TEM) specimens of coated ceramic fibers has been developed, which produces large electron transparent areas due to the minimal preferential milling of the fiber, coating, or epoxy matrix. Multiple individual fibers or tows are impregnated with a high-temperature epoxy and contained to assure a high fiber-to-epoxy volume ratio. The samples are then sectioned and mechanically thinned either parallel or normal to the fiber axes using a wedge polisher on diamond lapping films to achieve a thickness of less than 5 μ.m. The thinned sample is then ion-milled to electron transparency in less than 30 min, giving representative specimens of the coating, fiber, and coating-fiber interface. This technique is also well suited to preparing extremely flat specimens for scanning electron microscopy analysis of thin coatings. Examples of TEM sections of coated fibers prepared using this technique are presented. 相似文献
949.
The determination of the diffusion coefficient for water in various porosity cellulose acetate membranes by a gravimetric method, using a humidified carrier gas, is described. It was found to be impossible to obtain meaningful results for very porous membranes, although dense membranes gave limiting values of diffusion coefficient at high carrier gas velocities. This phenomenon is explained in terms of the dissipation of the heat of sorption by the forced convection provided by the carrier gas. The variation of diffusion coefficient with concentration of water in dense cellulose acetate is explained in terms of clustering of water molecules in the polymer at high concentration. 相似文献
950.
Guimes Rodrigues Filho Leandra Cardoso Toledo Daniel Alves Cerqueira Rosana Maria Nascimento de Assunção Carla da Silva Meireles Harumi Otaguro Sizue Ota Rogero Ademar Benévolo Lugão 《Polymer Bulletin》2007,59(1):73-81
Summary In this article, cellulose acetate produced through the homogeneous acetylation of sugar cane bagasse cellulose was used to
produce membranes, using poly(ethyleneglycol) 600 (PEG 600) as an admixture. The membranes were characterized using water
flux measurements (Payne’s cup), differential scanning calorimetry (DSC) and neutral red uptake (cytotoxicity). The results
showed that PEG 600 acts as a crystallinity inductor and/or pore former in the cellulose acetate matrix. The induction of
crystallinity is important for this system since it had not been reported on the literature yet. The results also demonstrated
that the studied membranes present a nontoxic behavior. 相似文献