Showing papers on "Catalyst support published in 1979"

Characterization of Molybdena Catalysts

Abstract: Publisher Summary The term molybdena is used in this chapter to denote a composite catalyst consisting of molybdenum oxide supported on an activated support, commonly alumina. Early it was found that certain transition metals, notably cobalt and nickel, promote the molybdena catalyst for hydrodesulfurization (HDS) reactions. The chapter discusses the various characterization techniques, which have been applied to this catalyst system. The chapter aims to relate what each technique reveals about the nature of the catalyst, and to present an overall picture of the state of the catalyst as it now appears. The chapter mentions some selective catalyst activity tests that were designed to give some fundamental insights into the catalyst state or active sites present. The chapter provides a comparison of their properties to the catalyst systems to assess to what degree they may be present in the catalyst.

Reforming with multimetallic catalysts

Abstract: A catalyst comprised of platinum, iridium, copper, selenium and halogen, composited with an inorganic oxide support or carrier, preferably alumina. The catalyst is one which possesses an intrinsically high activity, is stable, and can operate at reforming conditions at high severities.

Preparation of porous carbon

Abstract: Porous carbon, suitable for instance for chromatography and as a catalyst support is formed by depositing carbon into the pores of a porous inorganic template such as silica gel, porous glass or a porous oxide, e.g. alumina, and thereafter removing the template as by dissolution or evaporation. Carbon is preferably deposited as a polymerizable organic material that is polymerized in situ in the template pores and then pyrolyzed to carbon.

Catalyst for purifying exhaust gas and a process for manufacturing thereof

Abstract: A catalyst for the purification of exhaust gases, comprising: an active component of Pt, Pd or mixtures thereof deposited on a catalyst support of a carrier coated with a metal oxide having a spinel structure of the formula: MAl2 O4 wherein M is Sr, Mg, Cu, Mn, Mo, Zn, Fe, Ni or Co. The active component of the catalyst can optionally contain cerium.

Spectroscopic study on the surface structure and environment of fixed Mo catalysts prepared by use of Mo(π-C3H5)4

Abstract: The surface structure, the environment and the distribution of the active sites of fixed Mo catalysts were spectroscopically investigated and compared with those of conventional catalysts made by an impregnation method. The fixed catalysts were found to have the tetrahedral dioxostructure of six-valent molybdenum with coordination unsaturation, uniformly and atomically populated at silica or alumina surface, in a different environment from that of the impregnation catalysts. Such properties of molybdenum are thought to be essential factors for catalytic action in the abstraction of a hydrogen atom(hydride) from the C—H bond of a reactant. There are three different types of molybdenum species in the impregnation silica catalysts.

Characterization of a sulfur‐resistant methanation catalyst by XPS.

Abstract: A Ni–Cr on MgSiO3 catalyst has been developed by United Catalysts, Inc. This catalyst converts 60% of the input CO to CH4 after a heavy presulfiding treatment that reduces the CO conversion of conventional catalysts to less than 10%. The unsulfided conversion rate is better than 95%. X‐ray photoemission spectra obtained from a series of untreated, sulfided, and methanation‐tested Ni and Ni–Cr on MgSiO3 catalysts show the presence of nickel sulfide in catalysts which are deactivated by the sulfiding. Both nickel sulfide and nickel sulfate are found in the catalysts that retain appreciable methanation activity. The amount of sulfur in the active catalysts is also appreciably less than in the inactive catalysts. The relationship between the resistance to sulfur poisoning and the presence of Cr and MgSiO3 is discussed.

Process for regenerating fluidizable particulate cracking catalysts

Abstract: A process and apparatus for regenerating fluidizable particulate cracking catalysts wherein a mixture of spent catalyst particles contaminated with carbonaceous deposits from a catalytic cracker and sufficient hot regenerated catalyst particles to bring the temperature of the mixture to the minimum temperature at which rapid oxidation of the carbonaceous deposits will be induced, are entrained in a high velocity gas stream containing sufficient oxygen to oxidize substantially all of the carbonaceous deposits on the spent catalyst particles to carbon dioxide and carbon monoxide and the resulting dilute phase catalyst particle stream is passed upwardly through a primary regeneration zone wherein the carbonaceous deposits are oxidized and the catalyst particles regenerated to a carbon content of less than 0.1%; the catalyst particles being passed to a dense phase fluidized bed of regenerated particles in a secondary regeneration zone where the combustion heat is absorbed by the particles and residual carbon monoxide is oxidized to carbon dioxide to produce flue gases containing less than 1,500 ppm carbon monoxide.

Passivation of cracking catalysts

Abstract: A method for passivating a catalyst utilized to crack hydrocarbon feedstock to lower molecular weight products in a reation zone is disclosed, where the feedstock contains at least two metal contaminants selected from the class consisting of nickel, vanadium and iron and where these contaminants become deposited on the catalyst. The method comprises passing the catalyst from the reaction zone through a reduction zone maintained at an elevated temperature for a time sufficient to at least partially passivate the catalyst.

Synergistic effect of composite catalysts on the direct hydrogenation of carbon

Abstract: The catalytic reaction between an active carbon and hydrogen has been investigated with the objective of finding the effective catalyst system and reaction mechanism in agreement with the gas–solid catalytic reaction. The three-component catalyst, Ni or Co as the catalyst substrate combined with a small amount of La2O3 and a platinum group metal such as Ru, exerted a synergistic effect on the hydrogenation of the active carbon at temperatures within the range 300–800°C. The reaction mechanism, consisting of two-step hydrogen spillover to the active carbon through the platinum group metal and Ni + La2O3, is proposed on the basis of kinetic and adsorption data and micro-morphological observation.

Methanation of carbon monoxide over tungsten carbide-containing alumina catalyst for methanation of carbon monoxide

Abstract: A process of preparing methane-containing gas comprising contacting carbon monoxide and hydrogen in the presence of a catalyst containing tungsten carbide. Various tungsten carbide-containing alumina gel catalysts are also disclosed.

Catalyst carrier, catalyst and their manufacturing process

Abstract: A porous catalyst carrier refractory material with its pores containing internally deposited active alumina, its total pore volume being 005-050 cc/g, its average pore diameter 005-50μ and its specific surface area 3-60 m 2 /g and a method of making it

Aluminum phosphate-alumina compositions and catalysts comprising the same

Abstract: High surface area aluminum phosphate-alumina compositions are prepared by reaction of a mixture comprising an aluminum alkoxide and an organic phosphate such as trialkyl or triaryl phosphate, in the presence of moist air to form a precipitate, separating the precipitate from the mixture, drying and calcining the precipitate and recovering a high surface area aluminum phosphate-alumina product which can be used as catalyst support or catalyst component, especially for hydrocarbon treating and conversion processes.

Method for the activation of phosphomolybdic acid based catalysts

Abstract: The present invention relates to a method for the activation of PMA based catalysts by treating the catalyst precursor with a nitrogen-containing compound such as an oxide of nitrogen gas or a nitrogen acid such as nitric or nitrous at a temperature of from about 125° C. to about 400° C. The method can be employed in a reactor by loading the catalyst precursor, adjusting the reactor temperature to one suitable for activation and optionally sweeping the reactor with an inert gas followed by the treating step. The method herein permits faster, lower temperature catalyst activation than when air activation is employed giving higher oxidative conversion yields and prolonged catalyst life.

Reforming with an improved platinum-containing catalyst

Abstract: An improved process for the reforming of a hydrocarbon stream, which process comprises contacting said hydrocarbon stream under reforming conditions and in the presence of hydrogen with a catalyst which comprises platinum, rhenium, a small amount of palladium, and combined halogen on a refractory inorganic oxide, such as an alumina, and which has not been presulfided. The improvement comprises a rhenium-containing catalyst which has not been presulfided and which contains a small amount of palladium, i.e., about 0.05 wt. % to about 1 wt. % palladium. The feedstock being reformed can contain up to about 50 ppm sulfur.

Converting homogeneous to heterogeneous catalysts

Abstract: Homogeneous transition metal complex catalysts for organic industrial processes are converted to catalysts which are heterogeneous with respect to the reactants, and which have substantially equal catalytic activity to the homogeneous catalysts. This is done by reacting a normally homogeneous transition metal complex catalyst with a metal bridging ligand which substantially duplicates the ligand moiety of the metal complex, to provide a polymerized, normally solid, heterogeneous phase, transition metal complex catalyst.

Attrition resistant-higher active component fluid bed catalysts

Abstract: A method for preparing attrition resistant, high percentage active component catalysts comprises using two types of silica, one of which is fumed silica, in a two stage catalyst preparation.

Hydrocarbon cracking using combined perovskite and zeolite catalyst

Abstract: A perovskite is added to a conventional hydrocarbon cracking catalyst comprising a zeolite and an inorganic oxide gel matrix. The perovskite is present in said catalyst in an amount up to about 10 weight percent based on the total catalyst.

Attrition resistant catalysts

Abstract: Catalysts having improved attrition resistance are produced by incorporating a substantially uniform appearing coating of completely calcined, catalytically active oxide material onto an inert porous support containing sorbed aqueous silica sol. Such catalysts are useful in the gas phase oxidation of unsaturated aldehydes to unsaturated acids, especially acrolein to acrylic acid.

Catalyst for concentrating hydrogen isotopes and process for producing a support therefor

Abstract: OF THE DISCLOSURE A catalyst for concentrating hydrogen isotopes for use in performing hydrogen isotopes exchange between gaseous hydrogen and liquid water, the catalyst comprising a support of porous polytetrafluoroethylene having a total specific surface area of 2 to 80 m2/g as a result of mixing therewith 0.5 to 15%by weight of fluorocarbon or a porous styrene polymer or styrene/divinylbenzene copolymer having a specific surface area of at least 150 m2/g, and deposited on the support particles of at least one element selected from Group VIII of the Periodic Table. A method for producing a support of porous polytetra-fluoroethylene for such catalyst is also disclosed.

Polymerization of olefins with dual, independently supported catalysts

Abstract: Alpha-olefins are polymerized in the presence of at least two independently supported catalysts, one of which is an inorganic halide supported titanium and/or vanadium Ziegler type catalyst and at least one other is inorganic oxide supported, chromium catalyst. This dual catalyst increases catalyst efficiency and/or provides more flexible control of the properties of the resulting polymers.

Catalysts for hydrocarbon treating processes

Abstract: A catalyst is provided which comprises a composition comprising a catalytic metal component, carbon and hydrogen deposited on a low surface area aluminum alloy powder support prepared by atomizing the metal alloy Hydrocarbon treating and conversion processes utilizing the catalyst are also provided The catalyst is particularly suitable for slurry processes

Alumina-containing methanation catalysts

Abstract: It was previously found that a catalyst containing molybdenum and at least one element of the lanthanide or actinide groups or mixtures thereof, at a temperature of from 300° C. to 600° C. and a pressure of from 100 psig to 2,000 psig was a superior catalyst for the production of methane from a feed mixture containing hydrogen, carbon monoxide and gaseous compounds of sulfur. It has now been discovered that although the presence of alumina as an additional component had not been well characterized, it gives advantageous results when present in these methanation catalysts. Experimental data have shown that when alumina is added in small proportions to the molybdenum containing catalysts it results in further increased activity. Substantially the same temperatures, pressures and feed streams are used as in the process which does not employ the alumina in the catalysts.

Method for the preparation of cis-alkylcyclohexanols

Abstract: An improved method for selectively hydrogenating an alkylphenol to produce the corresponding cis-alkylcyclohexanol by employing a solid catalyst is disclosed. The catalyst useful in this method is a ruthenium catalyst supported on an alumina carrier. This catalyst exhibits excellent reactivity, selectivity and durability in the catalytic hydrogenation compared to conventional rhodium or ruthenium catalysts, such as ruthenium oxide and ruthenium catalysts supported on carbon. The alkylcyclohexanol product contains so much cis-isomer that it is suitable as such for use as an intermediate for the synthesis of varous chemicals, such as perfumes.