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Showing 1 to 20 of 41 for “"Silica alumina"”.
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The oligomerisation of propene over nickel oxide silica alumina
… for the preparation of a nickel oxide sil ica alumina catalyst. The propene oligomerisation activity and the selectivity of the catalysts prepared by homogeneous decomposition deposition (HDD) were investigated and compared with nickel oxide silica alumina catalysts prepared by the techniQues …
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The application of silica-alumina catalysts to a Friedel-Crafts type reaction
… effect of activated clays and the type of silica-alumina catalysts used in the cracking of petroleum, when used in a Friedel-Crafts type reaction. The limited amount of work which has been done so far indicates that it might be economical to use a synthetic silica-alumina type catalyst to …
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Anisotropic EPR and ENDOR studies of sulfur-containing heterocyclic compounds adsorbed on silica-alumina surfaces
… of an organic molecule adsorbing onto a silica-alumina surface is a topic of great interest. Many questions concerning exactly how this phenomenon occurs still remain unanswered. Although Electron Paramagnetic Resonance and Electron-Nuclear Double Resonance techniques are sensitive to the …
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Performance and mechanism on a high durable silica alumina based cementitious material composed of coal refuse and coal combustion byproducts
… dissertation is to investigate and develop a new silica-alumina based cementitious material largely using coal refuse as a constituent that will be ideal for durable construction, mine backfill, mine sealing and waste disposal stabilization applications. This new material is an …
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Dimerization of naphtha-range Fischer-Tropsch olefins into diesel-range products over zeolite H-ZSM-5 and amorphous silica-alumina
… phase, over zeolite H-ZSM-5 and an amorphous silica-alumina (ASA) catalyst. Both catalysts were in the form of extrudates.
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Reaction of meta-diisopropylbenzene on acid molecular sieves and synthesis of zeolites by a vapor phase transport method
… (hex and FAU), L, SAPO-37, and an amorphous silica-alumina at temperatures around 463 K in a flow-type fixed-bed reactor. A small amount of cracking is observed. The main reactions of meta-diisopropylbenzene are isomerization and alkylation. This alkylation is proposed as a new test reaction …
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The oligomerization of propene over cobalt catalysts
… supports investigated included activated carbon, alumina, silica alumina, synthetic mica montmorillonite, zeolite Y and NH₄⁺-ZSM-5. A cobaltmolybdenum hydrodesulphurization catalyst was also tested. The synthesis procedures used in this work included double ammoniation (Co-C), incipient wetness …
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X-band ENDOR and S-band ESEEM of paramagnetic disordered solids
… from perylene adsorbed on catalytically active alumina and silica-alumina surfaces were studied. Complex ENDOR spectra were obtained. The magnitudes of the principal elements of the anisotropic hyperfine matrix for each chemically distinct type of proton could be determined by means of a …
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Production of mid-chain branched detergent-range olefins over shape-selective acid catalysts
… of acid catalysts (MFI, BEA, TON and amorphous silica-alumina) were screened for the dimerization of 1-hexene, under generally mild conditions, viz. 150 - 170°C, 20 - 40 bar and 1 - 4h-1 WHSV. It was postulated that shape-selective catalysts with defined pore sizes might improve selectivity …
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Part~I: Determination of Quadrupole Couplings via L-Band, B(0) // B(1) EPR. Part~II: Surface Interactions of Perylene Adsorbed on Oxide Powders
… attention paid to contrasting the data from the alumina and silica-alumina substrates. The results suggest that the radicals, although themselves similar, occupy sites of significantly different environment.
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Methanol amination over hydrothermally treated zeolites RHO and Modernite
… or dimethyl ether and ammonia over amorphous silica-alumina. This process involves large separation and recycle units which are both costly and energy intensive as the separation requires azeotropic distillation at 15 bar. Methylamines can be formed over other solid acid catalysts with …
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Aqueous reactivity of glassy industrial byproducts in alternative cementitious systems
… necessary for GHG impact mitigation. Glassy silica-, alumina-, lime-, and/or alkali-rich industrial byproducts (IBs) exhibit the properties necessary to achieve emissions reductions while preserving final product attributes expected of cementitious binders. Research and industry have both …
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Shape-selective methylation of meta-cresol
… obtained over non shape-selective, amorphous silica-alumina.
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Experimental and Modeling Studies of the Methane Steam Reforming Reaction at High Pressure in a Ceramic Membrane Reactor
… and hydrogen selective membrane composed of silica and alumina was successfully prepared on a macroporous alumina support by chemical vapor deposition in an inert atmosphere at high temperature. Before the deposition of the silica-alumina composite, multiple graded layers of alumina were …
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Alkylation of phenol with methanol over H-ZSM-5, H-Beta, H-Mordenite, H-USY and H-MCM-22
… over aluminium oxides with strong acid sites, silica alumina, zeolites, aluminium phosphates and phosphoric acid-Kieselguhr catalysts. However, direct synthesis of high purity m-cresol and p-cresol is desirable due to the high costs of separating these two isomers. Thus to synthesize p-cresol, …
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Composite inorganic membranes for hydrogen reaction, separation and purification.
Silica-alumina composite membranes for hydrogen separation and high temperature chemical reactions were prepared using both conventional and modified dip-coating techniques. These were deposited on commercially available a.-alumina macroporous support of 10 millimetre (mm) outer diameter, 7 mm …
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Mixing of nanoparticles in a stirred tank in high pressure carbon dioxide
… the main goal of this work. Binary suspension of silica/alumina and silica/titania powders with the average primary particle sizes 16 nm (silica). 13 nm (alumina), and 21 nm (titania) was mixed in a 300 ml pressurized stirred tank at 45 C, both in supercritical and gaseous CO_2. The obtained …
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Fluidization of nanoparticles
… forces or changes in certain conditions. Silica, alumina, and titania nanoparticles, whose sizes range from 7 to 21 nm in diameter, are fluidized in a conventional gravity-driven bed, a vibrated bed, a magnetically assisted bed, a rotating bed, and a bed under supercritical conditions. The …
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