Showing papers on "Catalyst support published in 1985"

The Distribution of Active ingredients in Supported Catalysts Prepared by Impregnation

Abstract: Supported catalysts, one of the commonest forms of heterogeneous catalysts in practical use, consist of small crystallites of a catalytically active component dispersed in a porous support of high surface area. Impregnation of the support with an aqueous solution of a compound containing the appropriate catalytic component is an important and frequently used method of preparing this type of catalyst. A nonaqueous solution should be used if the sup port surface is hydrophobic or if hydrolysis of the support surface is to be avoided. In its simplest form, this impregnation method involves three steps: (1) contacting the support with impregnating solution for a certain period of time, (2) drying the support to remove the imbibed liquid, and (3) activating the catalyst by calcination, reduction, or other appropriate treatment.

Polymerization catalyst, production and use

Abstract: of the Disclosure Ethylene and alpha-olefins are homopolymerized or copolymerized with another olefin monomer in the presence of a catalyst system comprising an organo metal cocatalyst and a treated titanium-containing catalyst component, said titanium-containing catalyst component being obtained by reacting together a porous particulate material, an organic magnesium compound, an oxygen containing compound, a halogen, interhalogen compound or halosilane and titanium tetrachloride

Catalysts, method of preparation and polymerization processes therewith

Abstract: Method for the production of milled supports useful for the preparation of mono-1-olefin polymerization catalysts is provided by comminuting Mg(O)mX 2 -m or Mn(O)mX 2 -m, and high density ethylene polymer, optionally in the presence of an aromatic phenol and/or an aluminum halide to produce a composite catalyst support prior to further comminution with a tetravalent titanium halide to produce a first catalyst component and finally admixture of the first catalyst component with an organoaluminum catalyst compound. Polymerization process employing the novel catalyst system thus produced is also provided.

Design and Preparation of Impregnated Catalysts

Abstract: Solid catalysts in common use are typically in the form of small metal crystallites dispersed on the internal surface of the porous support. Advantages of these supported-metal catalysts lie in their high surface-to-volume ratio and the high thermal stability endowed by the dispersion. Such catalysts are commonly produced by liquid-phase impregnation in which a dry or wet pellet of the porous support is impregnated with a solution of a compound of the desired catalytic constituent. During impregnation and subsequent drying, small crystallites of the catalyst precursors are deposited on the internal surface of the support material. The impregnation and drying steps involve mass and /or heat transfer processes which often do not reach equilibrium, resulting in nonuniform concentration profiles of impregnant, or “impregnation profiles” along the radius of the support pellet.

Hollow porous microspheres as substrates and containers for catalysts and method of making same

Abstract: Hollow porous microspheres are used as substrates and containers for catalyst to make microsphere catalysts The hollow porous microspheres are made from dispersed particle compositions The microspheres have a single central cavity, have substantially uniform diameters and substantially uniform wall thickness and the walls of the microspheres have substantially uniform void content, ie, interconnecting voids, and have substantially uniform distribution of interconnecting voids The interconnecting voids in the walls of the microspheres are continuous and extend from the outer wall surface of the microsphere to the inner wall surface of the microsphere The microsphere catalysts are prepared by coating or impregnating the hollow porous microspheres with a catalyst or by applying a catalyst support to the microspheres and then coating or impregnating the microspheres and catalyst support with a catalyst The microsphere catalyst can also be prepared by filling the hollow porous microspheres with a catalyst or catalyst and catalyst support The microsphere catalyst can be treated to immobilize the catalyst and can be treated to provide the microsphere with a selective membrane The microsphere catalyst can be used for a wide variety of catalyst reactions

Fluorine-Promoted Catalysts

Abstract: It has been recognized for some time that the incorporation of fluorine in oxide catalysts (for example, alumina, silica-alumina, or zeolites) enhances their activity for acid-catalyzed reactions such as cracking, isomerization, alkylation, polymerization, and disproportionation. These reactions are thought to proceed via carbocation intermediates which are formed and stabilized on surface protonic sites. The incorporation of fluorine increases the activity by enhancing the acidic properties of the catalyst. Fluorine incorporated in an oxide catalyst replaces surface O or OH, and because fluorine is very electronegative, it polarizes the lattice more than the groups it replaces, and this increases the acidity of both protonic (Bronsted) and nonprotonic (Lewis) sites on the surface. As will be seen, pure alumina is inactive or only slightly active for acid-catalyzed reactions. In contrast, it has been shown repeatedly that fluorinated alumina is a very active, selective, and stable catalyst for su...

The structure of the Cu/ZnO catalyst by an in-situ EXAFS study

Abstract: Existence de trois formes de catalyseur, selon la temperature, au-dessous de 400°K, entre 400 et 500°K, au-dessus

Method of impregnating ceramic monolithic structures with predetermined amounts of catalyst

Abstract: A method for impregnating the interior skeletal structure of a ceramic monolithic catalyst support with a slurry of catalyst material is disclosed wherein a predetermined amount of catalyst slurry is metered into contact with a first end of the support. A cover is placed over the periphery of a second, opposite end of the support in sealing relation thereto to define a vacuum chamber adjacent to the second end. A vacuum is drawn on the cover to draw catalyst slurry into the skeletal structure from the second end whereby the interior skeletal structure is uniformly impregnated with the catalyst slurry.

Process for removing surface oxides from activated carbon catalyst

Abstract: An improved process is provided for the selective production of secondary amines and primary amines by bringing together under reaction conditions a tertiary amine or a secondary amine with oxygen or an oxygen-containing gas in the presence of an activated carbon catalyst, the improvement which comprises using an activated carbon catalyst wherein oxides have been removed from the surface of the carbon.

Phosphorus-modified alumina composite, method of manufacture and use thereof

Abstract: A novel phosphorus-modified alumina composite comprising a hydrogel having a molar ratio on an elemental basis of phosphorus to aluminum of from 1:1 to 1:100 together with a surface area of about 140 to 450 m2 /gm is defined. The composite is prepared by admixing an alumina hydrosol with a phosphorus-containing compound to form a phosphorus-modified sol and gelling said admixture. The phosphorus-modified alumina composite is useful as a catalyst support for various catalytic reactions.

Nickel/alumina catalyst, its preparation and use

Abstract: The invention provides a nickel/alumina catalyst, with an atomic ratio of nickel/aluminium between 10 and 2, an active nickel surface area between 70 and 150 m2/g nickel and an average pore size, depending on the above atomic ratio, between 4 and 20 nanometers. Preferably the nickel/aluminium atomic ratio is between 10 and 4.Preferably the catalyst has a specific porous structure. The invention also provides a method for preparing the catalyst by a two step process involving precipitating nickel ions and adding during a second, so-called ageing step a soluble aluminium compound. The catalyst is useful for hydrogenating unsaturated organic compounds in particular oils.

Attrition resistant catalysts, catalyst precursors and catalyst supports and process for preparing same

Abstract: This invention relates to highly attrition resistant catalysts, catalyst precursors and catalyst supports and to processes for making and using them.

Magnesium halide catalyst support and transition metal catalyst prepared thereon

Abstract: OF THE DISCLOSURE A magnesium halide catalyst support is prepared by combining a magnesium component represented by the general formula R2Mg?xAlR'3 wherein R is a hydrocarbyl or a hydrocarbyloxy group; R' is a halide, hydrocarbyl, a hydrocarbyloxy, a carboxyl or an acyl group; and x has a value such that the atomic ratio of Al:Mg is 0.025:1 to 0.25:1 with a non-metallic halide source under conditions such that the reaction temperature does not exceed 60°C. The invention also concerns a magnesium halide supported transition metal catalyst wherein the transition metal component is a compound of the formula Tm(OR)yXy-x wherein Tm, R, X, y and x are as defined in the specification and a process for polymerizing one or more olefins using the aforementioned magnesium halide supported catalyst.

Ordered ternary fuel cell catalysts containing platinum and cobalt and method for making the catalysts

Abstract: A ternary alloy catalyst for the electrochemical reduction of oxygen is disclosed. Various methods of making the catalyst are developed. The catalyst has an ordered structure which improves stability and the specific activity of the catalyst.

Process for presulfurizing a hydrogen treatment catalyst

Abstract: The invention concerns a process for sulfurizing a catalyst, particularly a refining catalyst comprising a carrier and active metal oxides. In a first step, a sulfur compound mainly consisting of organic polysulfide is introduced into the catalyst mass. A second step consists of first sulfurizing, in the absence of hydrogen, the active metal oxides at a temperature lower than 275° C. and then activating the catalyst at a temperature higher than 275° C. The present invention concerns a process for presulfurizing a hydrocarbon treatment catalyst and/or preconditioning a catalyst in view of subsequent presulfurization.

Hydrotreating process employing a three-stage catalyst system wherein a titanium compound is employed in the second stage

Abstract: The catalytic hydrotreating of a residual oil-containing feedstream is carried out in a multi-catalyst bed in which the feedstream is first contacted with a catalyst bed which comprises of alumina, cobalt, molybdenum and nickel. The feedstream is then contacted with a second catalyst bed which contains a catalyst comprising alumina to which molybdenum, titanium and nickel have been added, followed by a third catalyst bed which contains a catalyst comprising alumina to which molybdenum and nickel have been added.

Process for preparing a supported catalyst for the oxydehydrogenation of ethane to ethylene

Abstract: A process for low temperature oxydehydrogenation of ethane to ethylene uses an improved supported catalyst produced by impregnating the support with the soluble portion of a precursor catalyst solution and then activating the impregnated support. The activated impregnated support provides good selectivity to ethylene and avoids the problems which can arise from impregnation of the support with the soluble and insoluble portions of a precursor catalyst solution.

Three-way catalysts of improved efficiency

Abstract: A three-way catalyst of improved efficiency suitable for simultaneously oxidizing both gaseous hydrocarbons and carbon monoxide, while reducing nitrogen oxides is disclosed. The three-way catalyst includes alumina, a platinum group metal and a rare earth metal oxide having deposited thereon in intimate contact therewith a p-type metal oxide.

Multimetallic pillared interlayered clay products and processes of making them

Abstract: This invention is a composition of matter made up of an expanded smectite clay having multi-metallic pillars separating the clay layers. The expanded clay may be used as a shape selective catalyst, catalyst support, or as an adsorbent material. More particularly, this invention relates to expanded smectite clays wherein the pillars are made up of aluminum and one or more transition metals.

Multi-stage Fischer-Tropsch process

Abstract: A multi-stage catalyst system is disclosed for the production of waxes in a Fischer-Tropsch process while producing relatively low quantities of methane. A first catalyst converts CO and H 2 into olefins, while a second catalyst converts the olefin, additional hydrogen and CO into higher molecular weight paraffin.