Catalysts, carriers for

First investigations of hydrolysis of aluminum alkoxides were performed in the 1950s and 1960s [1252, 285]. Stolarek [1536] studied hydrolysis reactions with the aim of the preparation of aluminum oxide as a carrier for catalysts. 

Use Decolorizing of oils and other liquids, oil-well drilling muds, insecticide carrier, floor-sweeping compounds, cosmetics, rubber filler, carrier for catalysts, filtering medium. 

Soluble polymers may also serve as carriers for catalysts and other auxiliary reagents. In this form they can be easily separated from the reaction products by simple precipitation of the polymer. Thus, a Sharpless asymmetric dihydroxylation with PEG-bound (DHQD)2PHAL (bis-ether of 1,4-dihydroxyphthalazine and dihydroquinidine) of various olefins gave the corresponding diols in good yields with high enantiomeric excesses [74]. 

Other possible carriers for catalysts are asbestos, pumice, kieselgur, silica gel, silica, active charcoal, and oxides, carbonates, and sulfates of magnesium, calcium, barium, zinc, aluminum, iron, chromium, and zirconium. Details for the preparation of palladium catalysts on barium sulfate have been recorded by Mozingo.137... 

The preparation of a mixed silica-alumina oxide by a microemulsion-mediated process has been reported . In this work, porous particles with a spherical morphology were obtained. This material can be used as a carrier for catalysts or as a precursor of ceramic materials. 

The inner surface of aerogels is more accessible to gas molecules than that of xerogels, with much lower porosity. Thus, aerogels are much better suited as catalysts or as carriers for catalysts [81,82]. This important application was one of the main reasons for the comeback of aerogels at the end of the 1960s. 

Dr. Rodney Delano Bagley of Messrs. Coming Glass Works applies for a patent to extmde honeycombs (carriers for catalyst converters) Patents are granted in Japan for the extrusion of ceramic catalyst converters... 

A solvent is needed as the carrier for catalyst or initiator feeds or as the reactor diluent for the solution and slurry suspension processes, while a comonomer is used to control the polymer density of the final product. In principle, the more volatile the hydrocarbon solvent and comonomer, the easier the separation from the polymer will be. However, there are some practical limitations ... 

A monolith or parallel passage reactor contains a solid construction with parallel channels, usually with a cross sectional area of a few square mm each. They can be manufactured either by drilling parallel holes in a solid block, or by a ceramic process starting with a pile of layers that look like corrugated cardboard, made of clay, which is then baked. The latter type is used as a carrier for catalysts, and applied where a low gas pressure drop is essential, e.g., in automobile exhaust gas purification. The mass transfer rates in such monoliths can be calculated easily from the equations describing mass (and heat-) transfer in straight tubes, see eqs. (4.24), (4.28) and (4.29). 

A. also serves as a catalyst and carrier for catalysts and is an important - mining chemical in gold recovery. 

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