Showing papers on "Catalyst support published in 1982"

Carbon Deposition in Steam Reforming and Methanation

Abstract: Deactivation of supported metal catalysts by carbon or coke formation is a problem of serious magnitude in steam reforming, methanation, and other important catalytic processes. Its causes are generally threefold: (1) fouling of the metal surface, (2) blockage of catalysts pores and voids, and/or (3) actual physical disintegration of the catalyst support. Since loss of catalytic activity and physical destruction of the catalyst by carbon deposits can occur rapidly (within hours or days) under unfavorable conditions, understanding and control of these effects are of major technological and economical importance.

Heterogeneous catalysis on the molecular scale

Abstract: The techniques of modern surface science permit the study of the structure, the composition, and the oxidation states in the topmost surface layer. A new instrument has been developed for the combined determination of the kinetic parameters of catalytic surface reactions at high pressures (atmospheres), and for surface characterization at low pressures (approx. 10/sup -9/ torr) by using small area (approx. 1 cm/sup 2/) model catalysts. Single-crystal catalyst studies reveal the structure sensitivity of most catalytic reactions. During hydrocarbon conversion, a carbonaceous deposit forms on the catalyst surface whose bonding and stoichiometry influences the surface reactions. A molecular model of the working metal catalysts for hydrocarbon reactions has been proposed. The oxidation states of surfaces atoms also markedly influence the rate and selectivity of catalyzed surface reactions. Using the molecular ingredients of hetergeneous catalysis that have been identified now makes it possible to build new, high-technology catalysts. 15 figures, 1 table.

Platinum group metal catalyst on the surface of a support and a process for preparing same

Abstract: Platinum or other platinum-group metals can be deposited substantially on the surface only of pellets of a refractory catalyst support by impregnation with an aqueous solution of such as hexammonium platinum tetrasulfite. The resulting catalysts contain relatively small total amounts of platinum-group metal positioned primarily at the surface, yet are as highly active as catalysts uniformly impregnated throughout the body of the pellet and containing much larger amounts of platinum-group metal. The catalyst further can contain thenium.

Catalysts for para-ethyltoluene dehydrogenation

Abstract: Para-ethyltoluene dehydrogenation catalyst compositions and processes for using such catalysts are provided. The catalyst compositions comprise a catalytically active iron compound, e.g., iron oxide; a potassium catalyst promoter, e.g., potassium carbonate; an optional chromium compound stabilizer, e.g., chromic oxide, and a gallium compound, e.g., gallium trioxide. Utilization of particular amounts of gallium compound in dehydrogenation catalyst compositions of this type will provide a catalyst especially suitable for promoting the selective dehydrogenation of para-ethyltoluene to form para-methylstyrene with sustained catalyst activity, with minimized aromatic ring loss and with minimal formation of popcorn polymer from the reaction effluent.

Ceramic honeycomb catalyst support coated with activated alumina

Abstract: A catalyst support provided with an activated alumina layer which is formed on the surface of the ceramic honeycomb structure is disclosed. The catalyst support of the present invention is formed of ceramic such as cordierite, of which coefficient of thermal expansion is lower than alumina and is provided with microcracks which occur when the honeycomb structure is formed. The activated alumina layer is formed on the surface of the catalyst support without filling the microcracks occurred therein. For example, the activated alumina layer is formed by adhering the activated alumina particulates to the surface of the honeycomb structure and firing the structure together with the activated alumina particulates after the microcracks occurred in the honeycomb structure are filled with such a material as to be burnt away at a temperature lower than the sintering temperature of activated alumina.

Three-catalyst process for the hydrotreating of heavy hydrocarbon streams

Abstract: There is disclosed a process for hydrotreating a heavy hydrocarbon stream containing metals, asphaltenes, nitrogen compounds, and sulfur compounds to reduce the contents of these contaminants. The process comprises contacting said stream in the presence of hydrogen and under suitable hydrotreating conditions in sequence with a first catalyst in a first reaction zone, a second catalyst in a second reaction zone, and a third catalyst in a third reaction zone. The first catalyst comprises a Group VIB metal and/or a Group VIII metal on a porous inorganic oxide support; the second catalyst consists essentially of at least one hydrogenation metal selected from Group VIB deposed on a support material comprising alumina; and the third catalyst comprises a hydrogenating component comprising molybdenum, chromium, and cobalt on a large-pore, catalytically-active alumina. Each catalyst has specific physical properties.

Phosphorus-containing catalyst

Abstract: A phosphorus-containing low alkali metal content zeolitic catalyst made from a clay starting material is provided. The catalyst is obtained by contacting a partially cation exchanged calcined zeolite-containing catalyst with a dihydrogen phosphate anion or a dihydrogen phosphite anion. A hydrocarbon catalytic cracking process utilizing the phosphorus-containing catalyst is also provided.

Phosphated alumina or aluminum phosphate chromium catalyst

Abstract: A catalyst system suitable for olefin polymerization comprising a catalyst component made up of chromium on a phosphated alumina or low phosphorus aluminum phosphate base and optionally an organometal cocatalyst. The resulting catalyst is particularly sensitive to the effects of hydrogen as a molecular weight control agent, thus allowing the production of polymers of having a melt flow varying over a wide spectrum utilizing the same catalyst.

High surface area nickel aluminate spinel catalyst for steam reforming

Abstract: A high surface area nickel aluminate spinel formed on alumina, prepared by a specified method and useful as catalyst support and as catalyst for hydrocarbon treating and conversion processes is provided. A steam reforming process utilizing the nickel aluminate spinel on alumina as catalyst is also provided.

Zeolite L catalyst for reforming

Abstract: An improved reforming catalyst employing a zeolite L support is provided by soaking the zeolite L in an alkali solution having a pH of at least 11 for a time and at a temperature effective to increase the period of time over which the catalytic activity of the catalyst is maintained.

Catalyst, method for the treatment of a gaseous mixture and use of the catalyst for selectively hydrogenating acetylene

Abstract: A catalyst and process for the selective hydrogenation of acetylene, said catalyst comprising palladium and silver with the palladium concentrated as a skin and the silver distributed throughout.

Process for preparing a polymerization catalyst and preparation of ethylene polymers with this catalyst

Abstract: Process for preparing and treating a chromium-containing catalyst so that when the catalyst is activated the risk of explosion is substantially reduced. The catalyst comprises a complex of chromium and optionally other transition metal complexes reacted with one or more organometallic compounds of a metal of group II or III of the periodic table, which metal contains hydrocarbyl groups of 1-20 carbon atoms. The reaction product is applied to an inert inorganic support to form the catalyst component which is deactivated by treatment with oxygen or an alcohol to modify or replace residual hydrocarbyl groups. The catalyst component may be activated to form the catalyst by heating in the range 200°-1200° C. The catalyst is used to catalyze a polymerization of alpha-olefins.

Copper catalyst compositions for fluid-bed oxyhydrochlorination of ethylene

Abstract: A fluidizable catalyst composition is provided having cupric chloride deposited on a fluidizable, modified gamma alumina support in which the support has incorporated, prior to the deposit of copper, from 0.5% to 3.0% by weight based on the weight of the support of at least one metal selected from the group consisting of potassium, lithium, rubidium, cesium, alkaline earth metals, rare earth metals, or combinations thereof. Such catalyst compositions are extremely useful as the fluid bed catalyst in the vapor phase oxyhydrochlorination reaction of ethylene, oxygen and hydrogen chloride to produce 1,2-dichloroethane. The use of the catalysts results in improved EDC efficiency based on ethylene and avoids operating problems caused by stickiness of the catalyst in the fluid bed. Incorporation of a combination of potassium and barium in the fluidizable gamma alumina support, prior to deposit of the copper, produces an excellent catalyst for a fluid bed ethylene oxyhydrochlorination process in which the vent gases from the process are recycled.

Process for catalytic dehydration of ethanol vapor to ethylene

Abstract: Process for catalytic dehydration of ethanol vapor to ethylene is provided which is carried out in the presence of water vapor, the mixture of ethanol and water vapor being contacted with the catalyst bed containing a substituted phosphoric acid catalyst The catalyst comprises a catalyst support having absorbed thereon a substituted phosphoric acid in which one of the hydroxyl groups thereof has been replaced by a hydrophobic organic group containing from 4 to 22 carbons

Catalyst and catalyst support compositions

Abstract: Cracking catalysts or catalyst supports prepared from mixtures comprising colloidal alumina, colloidal silica, a particulate weighting agent, and/or an active catalytic component possess excellent catalytic and physical properties. The catalysts in accordance with the invention also show excellent resistance to metal poisoning, and are also highly useful in non-cracking and/or hydroconversion processes.

Extending isomerization catalyst life by treating with phosphorous and/or steam

Abstract: There is disclosed a method for decreasing catalyst coking and extending the usable catalyst life by pre-treatment of the catalyst with steam and/or a phosphorus-containing compound. Catalysts benefiting from such pre-treatment comprise crystalline zeolites characterized by a silica to alumina mole ratio of at least 12 and a constraint index, as herein defined, within the approximate range of 1 to 12.

Catalyst regeneration procedure

Abstract: Supported multi-metallic platinum-containing hydrocarbon conversion catalysts which are at least partially deactivated due to the deposition of carbonaceous residues thereon during contact with hydrocarbons are regenerated by (1) contacting the catalyst with oxygen to burn at least a portion of the carbonaceous residues from the catalyst, (2) contacting the carbonaceous residue depleted catalyst with hydrogen at an elevated temperature to convert a substantial portion of the non-platinum component present in the catalyst to its metallic form, (3) contacting the reduced catalyst with dry hydrogen halide in the absence of oxygen, (4) treatment of the hydrogen halide treated catalyst with chlorine, and (5) reduction of the chlorine treated catalyst with a reducing agent, such as hydrogen.

Amorphous silica based catalyst and process for its production

Abstract: This invention relates to a catalyst for use in the direct conversion of synthesis gas to olefinic hydrocarbons in good yield. It also relates to a process for producing the catalyst. The catalyst comprises a highly porous amorphous silica support on which is deposited one or more monolayers of silica. The catalyst is then impregnated with a transition metal. The monolayer of silica is formed by the hydrolysis of a compound such as ethyl orthosilicate while it is adsorbed onto the support.

Polymerization with a silica base catalyst having titanium incorporated through use of peroxide

Abstract: A silica composition having a high concentration of titanium is produced by solubilizing a titanium compound by combining same with a peroxide such as hydrogen peroxide. In a preferred embodiment, the peroxide is combined with the acid typically used in producing a gel from the combination of a silicate solution and an acid although the solubilizing component can also be used to simply impregnate particulate silica. The resulting composition has a high titanium content and an unusual pore structure makes it ideally suited as a catalyst base. When contemplated as a catalyst base, chromium can simply be coprecipitated with the silica and titanium. The resulting catalyst is ideally suited for the polymerization of olefins under slurry conditions.

Passivation of metal contaminants on cracking catalyst

Abstract: A contaminating metal on a cracking catalyst used for the cracking of hydrocarbons is passivated by contacting the catalyst with a hydrocarbon gas or mixture of gases comprising molecules of three carbon atoms or less at passivation reaction conditions prior to the cycling of the catalyst to the cracking zone. The cracking catalyst comprises crystalline aluminosilicate contained in a substantially alumina-free inorganic oxide matrix.

Catalyst for production of gas enriched with hydrogen

Abstract: PURPOSE: To provide a catalyst for production of a gas enriched with H 2 is provided with high activity, high selectivity and a long service life, by depositing the oxide f copper, zinc and chromium on a carrier. CONSTITUTION: A carrier of alumina or the like is immersed in an aq. nitrate soln., etc. of active metals such as copper, zinc and chromium and is dried and calcined, whereby the oxide of copper and zinc or the oxide of copper, zinc and chromium is deposited thereon and a catalyst for production of a gas enriched with H 2 is obtained. The catalyst active component is dispersed satisfactorily in the carrier of such catalyst and there is no crystallization of the catalyst active component; therefore, the catalyst has excellent durability. The catalyst has high activity at low temp. and excellent selectivity as well. COPYRIGHT: (C)1983,JPO&Japio

Process and catalyst for the conversion of carbo-metallic containing oils

Abstract: An improved process and catalyst for economically converting carbo-metallic oils to lighter products. This process is practiced in accordance with effective metals management, carbon management and catalyst activity management combined with feed atomization-vaporization, efficient stripping of carbonaceous material from the coked catalyst, exothermic and endothermic removal of hydrocarbonaceous material to effectively maintain the RCC unit in heat balance. This reduced crude cracking process is practiced with a new and improved catalyst composition identified as RCCC-1 Special that is characterized by the following composition; at least 30 wt % rare earth exchanged "Y" faujasite crystalline zeolite with a silica to alumina ratio of at least 5 of a high lanthanum to cerium ratio and residual sodium content less than 0.30 wt %, is provided with a pore volume greater than 0.35 cc/gm. and comprises a clay matrix material that may or may not be acidic with pore size openings in the range of 500 to 2,000 angstroms. The RCCC-1 Special can contain metal promoters to catalyze the endothermic removal of coke and the partial removal of hydrogen present in the carbonaceous material with carbon dioxide. In addition, metal additives to passivate and immobilize vanadium are contemplted.

Process and catalyst for the conversion of oils that contain carbon precursors and heavy metals

Abstract: An improved process and catalyst for economically converting carbo-metallic oils to lighter products. This process is practiced in accordance with effective metals management, carbon management and catalyst activity management combined with feed atomization-vaporization, efficient stripping of carbonaceous material from the coked catalyst, exothermic and endothermic removal of hydrocarbonaceous material to effectively maintain the RCC unit in heat balance. This reduced crude cracking process is practiced with a new and improved catalyst composition identified as RCCC-1 Special that is characterized by the following composition; at least 30 wt% rare earth exchanged "Y" faujasite crystalline zeolite with a silica to alumina ratio of at least 5 of a high lanthanum to cerium ratio and residual sodium content less than 0.30 wt%, is provided with a pore volume greater that 0.35 cc/gm and comprises a clay matrix material that may or may not be acidic with pore size openings in the range of 500 to 2,000 angstroms. The RCCC-1 Special can contain metal promoters to catalyze the endothermic removal of coke and the partial removal of hydrogen present in the carbonaceous material with carbon dioxide. In addition, metal additives to passivate and immobilize vanadium is comtemplated.