Abstract:
Granules based on aluminium oxide having the characteristics: 1 Average grain diameter:5.0 to 150nullm Tamped density:300 to 1200g/l The granules are produced by dispersing aluminium oxide in water, performing spray drying, optionally heat treatment and/or silanization. In silanized form, the granules have the following characteristics: 2 Average grain diameter:5 to 160nullm Tamped density:300 to 1200g/l Carbon content:0.3 to 12.0wt. % The granules are used inter alia as catalyst supports, in cosmetics, in toner powders, in paints and lacquers, as abrasives and polishing agents and as a raw material in the production of glass and ceramics.
Abstract:
The present invention relates to monolith catalysts comprising a catalytic metal deposited onto a coated monolith substrate comprising a wash coat applied to a monolith substrate wherein the monolith catalysts have a surface area ranging from 0.1 to 25 m2/gram as measured by adsorption of N2 or Kr using the BET method. The invention also relates to the coated monolith substrates used in such monolith catalysts. The monolith catalysts of the present invention are particularly suited toward use in hydrogenation processes which employ an immiscible mixture of an organic reactant in water.
Abstract:
Thermally stable transitional alumina particulates retaining high specific surface area after calcination at 1000null C. suitable for the use as catalysts or catalysts supports are produced by treating an aqueous solution containing Al3null and optionally a doping amount of La3null (e.g., 0.3 mol. %) with an anion-exchange resin to give a stable hydroxide sol followed by freeze drying of the sol and further thermal dehydration. The resultant stabilized transitional alumina retains high specific surface area at 1000null C., and additionally stabilization is achieved at very low levels of added La.
Abstract:
A honeycomb body made from a ceramic material with improved radial pressure resistance that is of cylindrical shape and features a first and a second end face and a cylindrical shell and that is traversed from one end face to the other by axially parallel channels formed by channel walls and distributed across the cross section of the honeycomb body in a regular grid pattern, in which design an outer marginal zone of the honeycomb body, the thickness of which amounts to several channel diameters, encloses a central area. The increase in radial pressure resistance of the honeycomb body is achieved by reinforcing the ceramic material of the cylindrical shell and of the channel walls in the outer marginal zone of the honeycomb body by depositing on or in it one or several inorganic substances for the purpose of increasing its mechanical stability.
Abstract:
Electric arc spraying a metal onto a substrate produces an anchor layer on the substrate that serves as a surprisingly superior intermediate layer for a catalytic material deposited thereon. Spalling of catalytic material is resisted even when subjected to the harsh conditions imposed by small engines or in a close-coupled position for a larger engine.
Abstract:
The present invention provides a process for the preparation of a catalyst having a high surface area and pore volume. The process includes freeze drying an intermediary of the catalyst. The present invention further includes a catalyst prepared by a process that includes the freeze drying step. The present invention also includes a catalyst having a high acidity, as indicated by having an ammonium desorption peak at greater than about 500null C. The prevent invention further includes a method of manufacturing isomerized organic compounds using the catalyst.
Abstract:
Apparatus for coating a support such as a monolithic catalyst support (5) comprises a dispenser (1) for dispensing a predetermined quantity of coating liquid, a containment (2) for the liquid and a source of vacuum (8, 9) which can be actuated to draw the entire quantity of coating liquid into the support (5). The apparatus and method are particularly useful for coating car catalysts without wastage and with increased design options.
Abstract:
A titania-coated honeycomb catalyst matrix is provided for the ultraviolet-photocatalytic oxidation of organic pollutants in a flowing fluid. A honeycomb-shaped skeletal structure (12) has a thin, lightweight substrate (18) of metal or ceramic, typically an aluminum alloy, and a surface coating (20) of photocatalyst, such as titania. The photocatalyst (20) is bonded to the substrate (18) via a thin oxide layer (18null) on the substrate. The oxide layer (18null) may be grown on the substrate. The photocatalyst coating (20) is made by mixing (30) titania powder in a TiO2 sol-gel to form a titania slurry. The substrate with oxide layer is coated (30) with the titania slurry and then heat treated (31). The photocatalyst coating (20) is typically applied to substrate sheets (40, 60, 62) preformed for assembly into a honeycomb-shaped skeletal structure (12) having an array of parallel cells (46, 46null). The coated sheets (40) may have troughs (42) and crests (42), and be stacked (34) with intermediate parting sheets (48). Alternatively, the coated sheets (60, 62) may be notched (64) and interfitted in nulleggcratenull fashion. The honeycomb-shaped structure (12) is housed in a frame (50), and one or more stabilizer members (52) fastened to the frame serve to limit displacement of the structure as may be caused by the flowing fluid (14).
Abstract:
The present invention provides metal-exchanged hexaaluminate catalysts that exhibit good catalytic activity and/or stability at high temperatures for extended periods with retention of activity as combustion catalysts, and more generally as oxidation catalysts, that make them eminently suitable for use in methane combustion, particularly for use in natural gas fired gas turbines. The hexaaluminate catalysts of this invention are of particular interest for methane combustion processes for minimization of the generation of undesired levels (less than about 10 ppm) of NOx species. Metal exchanged hexaaluminate oxidation catalysts are also useful for oxidation of volatile organic compounds (VOC), particularly hydrocarbons. Metal exchanged hexaaluminate oxidation catalysts are further useful for partial oxidation, particularly at high temperatures, of reduced species, particularly hydrocarbons (alkanes and alkenes).
Abstract:
Novel materials for chromatographic separations, processes for their preparation, and separation devices containing the chromatographic materials. In particular, the novel materials are porous inorganic/organic hybrid monolith materials, which desirably may be surface modified, and which offer more efficient chromatographic separations than that known in the art.