Abstract: A high-strength geopolymer hollow microsphere, a preparation method thereof and a phase change energy storage microsphere are provided, including: dissolving sodium hydroxide, sodium silicate and spheroidizing aid in water to form a solution A, and adding active powder to the solution A, stirring and uniformly mixing to form a slurry B, adding the slurry B to an oil phase, stirring and dispersing into balls, filtering to obtain geopolymer microspheres I, washing the geopolymer microspheres I, and then carrying out a high-temperature calcination to obtain the high-strength geopolymer hollow microspheres II; using the high-strength geopolymer hollow microsphere as a carrier, absorbing a phase change material into the carrier, and mixing a microsphere carrying the phase change material with an epoxy resin, adding a powder dispersant and stirring to disperse the microsphere, after the epoxy resin is solidified, screening the superfluous powder dispersant to obtain the phase energy storage microsphere.

Abstract: A layered catalyst reactor system and process for hydrotreatment of hydrocarbon feedstocks. The layered catalyst system reactors comprise vertical bed layers including a demetallization catalyst layer, multiple layers of supported hydrotreating catalyst layer, and multiple alternating layers of supported hydrocracking catalysts and self-supported hydrotreating catalysts. The arrangement of the catalyst layers mitigates the risk of temperature run-aways, with improvements in hydrotreatment performance.

Abstract: The present invention provides a means capable of suppressing the formation of fine particles in a method for producing a silica sol.

Abstract: An adsorbent composition for removing chlorides from hydrocarbon includes an adsorbent matrix and a metallic component. The metallic component forms an intimate complex with the adsorbent matrix. The adsorbent composition is characterized by pore size in the range of 20 ? to 120 ?. It is found that the amount of chlorides removed by the adsorbent composition from the hydrocarbon is in the range of 0.020 wt. % to 0.047 wt. %.

Abstract: Embodiments of processes and multiple-stage catalyst systems for producing propylene comprising introducing a hydrocarbon stream comprising 2-butene to an isomerization catalyst zone to isomerize the 2-butene to 1-butene, passing the 2-butene and 1-butene to a metathesis catalyst zone to cross-metathesize the 2-butene and 1-butene into a metathesis product stream comprising propylene and C4-C6 olefins, and cracking the metathesis product stream in a catalyst cracking zone to produce propylene. The isomerization catalyst zone comprises a silica-alumina catalyst with a ratio by weight of alumina to silica from 1:99 to 20:80. The metathesis catalyst comprises a mesoporous silica catalyst support impregnated with metal oxide. The catalyst cracking zone comprises a mordenite framework inverted (MFI) structured silica catalyst.

Abstract: A filter system for filtering a fluid stream is disclosed herein. The filter system includes a first fluid passage, a first chamber, a second chamber, an adsorbing media, and a second fluid passage. The first fluid passage is arranged such that a fluid stream can flow through the first fluid passage and into the filter system. The first chamber is arranged to hold suspended or dissolved solids, pollutants, and nutrients that are filtered from the fluid stream. The second chamber is positioned above the first chamber and in fluid communication with the first chamber. The adsorbing media is positioned in the second chamber. The second fluid passage is arranged such that filtered fluid from the fluid stream can flow out of the filtering system through the second fluid passage.

Abstract: Provided is an insolubilizing material for a specific toxic substance useful for insolubilizing a heavy metal or the like conducted by applying the insolubilizing material for a specific toxic substance to soil or on the surface of the soil. The insolubilizing material, for a specific toxic substance, is used in a manner so that soil does not reach a strongly alkaline region of a pH of 11 or more. The insolubilizing material for a specific toxic substance comprises an amorphous aluminum compound or a derivative thereof as a main component. The insolubilizing material functions as a solidifying material. The insolubilizing material also comprises gypsum obtained by adding and mixing, to the gypsum, the amorphous aluminum compound or the derivative thereof in a range from 0.5 to 60 mass parts relative to 100 mass parts of the gypsum. A method for improving soil using the insolubilizing material is also disclosed.

Abstract: Disclosed herein is a photocatalytic filter, which includes a plurality of cross-linked polymethyl methacrylate (PMMA)/ionic liquid (IL)/TiO2 nanocomposite pellets, and a photocatalytic vessel. The plurality of cross-linked PMMA/IL/TiO2 nanocomposite pellets is placed within the photocatalytic vessel. Each cross-linked PMMA/IL/TiO2 nanocomposite pellet includes a PMMA polymeric matrix, and a plurality of IL/TiO2 core-shell microspheres dispersed within the PMMA polymeric matrix. Moreover, each IL/TiO2 core-shell microsphere includes a core of IL and a shell of TiO2 nanoparticles.

Abstract: Embodiments of processes and multiple-stage catalyst systems for producing propylene comprising introducing a hydrocarbon stream comprising 2-butene to an isomerization catalyst zone to isomerize the 2-butene to 1-butene, passing the 2-butene and 1-butene to a metathesis catalyst zone to cross-metathesize the 2-butene and 1-butene into a metathesis product stream comprising propylene and C4-C6 olefins, and cracking the metathesis product stream in a catalyst cracking zone to produce propylene. The isomerization catalyst zone comprises a silica-alumina catalyst with a ratio by weight of alumina to silica from 1:99 to 20:80. The metathesis catalyst comprises a mesoporous silica catalyst support impregnated with metal oxide. The catalyst cracking zone comprises a mordenite framework inverted (MFI) structured silica catalyst.

Abstract: A method for forming substantially consistently-sized and substantially controllably-timed droplets is disclosed. An opening is provided through which a protrusion passes. The protrusion ends at a tip below the opening. A process liquid is provided to the opening at a controlled flow rate. The process liquid passes through the opening and flows along the protrusion, forming a droplet of the process liquid on the tip that reaches a substantially consistent droplet size and falls. The process liquid continues to pass through the opening at an even time interval based on the flow rate. In this manner, substantially consistently-sized and substantially controllably-timed droplets are formed.

Abstract: Disclosed herein is a simple process for functionalization/grafting of carbon microspheres obtained from bagasse with various active functional groups onto it and use of the same as catalyst for various organic reactions, having very high selectivity and conversion rate.

Abstract: We provide a mesoporous silicon material (PSi) prepared via a template-free and HF-free process. The production process is facile and scalable, and it may be conducted under mild reaction conditions. The silicon may be produced directly by the reduction of a silicon-halogenide precursor (for example, SiCl4) with an alkaline alloy (for example, NaK alloy). The resulting Si-salt matrix is then annealed for the pore formation and crystallite growth. Final product is obtained by removal of the salt by-products with water.

Abstract: A catalyst composition comprises (i) a support; (ii) a dehydrogenation component comprising at least one metal or compound thereof selected from Groups 6 to 10 of the Periodic Table of Elements; and (iii) tin or a tin compound, wherein the tin is present in an amount of 0.01 wt % to about 0.25 wt %, the wt % based upon the total weight of the catalyst composition.

Abstract: The invention concerns a process for preparing a solid comprising ZnO and a binder comprising the following steps: pre-mixing powders comprising at least one ZnO powder and at least one binder (step a), mixing the paste obtained (step b), extruding (step c) the paste obtained in step b), drying the extrudates, and calcining (step d) in a stream of gas comprising oxygen.

Abstract: Hollow conjugated polyelectrolyte (HCPE) microcapsules contain at least one conjugated polyelectrolyte and at least one other polyelectrolyte of complementary charge and the microcapsule has a hollow core. The conjugated polyelectrolyte is a polymer with a multiplicity of charged repeating units where a portion of the charged repeating units form a pi-conjugated sequence. The complementary polyelectrolyte is a polymer with a complementary charged repeating unit to the charged repeating units of the conjugated polyelectrolyte. The HCPE microcapsules can be formed by successively coating a sacrificial core with alternating layers of complementary polyelectrolytes, at least one of which is a conjugated polyelectrolyte. The sacrificial core can be removed to form the hollow center of a HCPE microcapsule.

Abstract: A method for preparing a catalyst having catalytically active materials selectively impregnated or supported only in the surface region of the catalyst particle using the mutual repulsive force of a hydrophobic solution and a hydrophilic solution and the solubility difference to a metal salt precursor between the hydrophobic and hydrophilic solutions. The hydrophobic solvent is a C2-C6 alcohol. The hydrophobic solvent is introduced into the catalyst support and then removed of a part of the pores connected to the outer part of the catalyst particle by drying under appropriate conditions. Then, a hydrophilic solution containing a metal salt is introduced to occupy the void spaces removed of the hydrophobic solvent, and the catalyst particle is dried at a low rate to selectively support or impregnate the catalytically active material or the precursor of the catalytically active material only in the outer part of the catalyst particle.

Abstract: The present invention concerns spheroidal alumina particles, catalysts comprising such particles as a support and a process for the production of spheroidal alumina particles, comprising the following steps: a) preparing a suspension comprising water, an acid and at least one boehmite powder for which the ratio of the crystallite dimensions in the [020] and [120] directions obtained using the Scherrer X-ray diffraction formula is in the range 0.7 to 1; b) adding a pore-forming agent, a surfactant and optionally water, or an emulsion comprising at least one pore-forming agent, a surfactant and water to the suspension of step a); c) mixing the suspension obtained in step b); d) shaping the spheroidal particles by the oil-drop method using the suspension obtained in step c); e) drying the particles obtained in step d); f) calcining the particles obtained in step e).

Abstract: The present invention relates to a method for preparing a nickel-based catalyst for steam carbon dioxide reforming (SCR) of natural gas using steam and carbon dioxide, more particularly to a method for preparing a nickel-based catalyst represented by Ni/?-Al2O3, which is prepared by supporting nickel on a spherical ?-alumina support having many acid sites at high density by repeating impregnation and drying tens of times. The catalyst prepared according to the present invention exhibits superior catalytic activity when used in steam carbon dioxide reforming reaction (SCR) even under harsh conditions of high temperature and high pressure and hardly exhibits carbon deposition due to superior durability.

Abstract: Ceramic catalyst carriers that are mechanically, thermally and chemically stable in a ionic salt monopropellant decomposition environment, high temperature catalysts for decomposition of liquid high-energy-density monopropellants and ceramic processing techniques for producing spherical catalyst carrier granules are disclosed. The ceramic processing technique is used to produce spherical catalyst carrier granules with controlled porosities and desired composition and allows for reproducible packing densities of catalyst granules in thruster chambers. The ceramic catalyst carrier has excellent thermal shock resistance, good compatibility with the active metal coating and metal coating deposition processes, melting point above >2300° C., chemical resistance to steam, nitrogen oxides and nitric acid, resistance to sintering to prevent void formation, and the absence of phase transition associated with volumetric changes at temperatures up to and beyond 1800° C.

Abstract: The present invention concerns a nano-structured composite material based on compositions of manganese and cerium, composed of aggregated composite nanospheres, ranging in size from 1 to 40 nm, of ultrafine crystalline nanoparticles of one or more compounds of cerium, dispersed in a metastable solid mixture of one or more sub-stoichiometric oxides of manganese, said sub-stoichiometric oxides of manganese comprising MeMnOz manganates, wherein 1?z?4, Me being constituted of one or more elements selected amongst alkali metals, alkaline earth metals, transition metals and rare earths, and in particular being constituted of one or more elements selected amongst Ce, V, Ti, Cr, Fe, Cu, Zn, Sn, Ga, Gd, Y, Zr, Al, Si, La, K, Li, Pb, Cs, or mixtures thereof; which can be used in the industry as redox catalyst and/or adsorbing filter of heavy metals, cyanides, sulfur compounds, pigments, dyes, polymers (PEG), phenols, alcohols, aldehydes and ketones, ethers, esters and carboxylic acids which are present both in contamin

Abstract: The present invention provides a hollow IM-5 molecular sieve sphere and the preparation process thereof. The process according to the present invention adds a relatively great amount of the surfactant of a cationic quaternary ammonium salt in the IM-5 molecular sieve system, to form a hollow IM-5 molecular sieve sphere via the micelle action by the surfactant, which structure benefits the mass transfer of the reaction process.

Abstract: A cobalt-based nano catalyst including a metal combination as a core and a porous material as a shell. The metal combination includes a first metal component Co, a second metal component selected from Ce, La, and Zr, and a third metal component selected from Pt, Ru, Rh, and Re. The catalyst includes between 10 and 35 wt. % of the first metal component, between 0.5 and 10 wt. % of the second metal component, between 0.02 and 2 wt. % of the third metal component, and a carrier. The carrier is a porous material such as nano silica or alumina. The carrier is in the shape of a spheroid, has a pore size of between 1 and 20 nm and a specific area of between 300 and 500 m2/g. The active component of the catalyst has a particle size of between 0.5 and 20 nm.

Abstract: The present invention refers to titanium oxide microspheres having photocatalytic properties which can, for example, be used in a method for cleaning wastewater which uses a submerged membrane reactor.

Abstract: The present invention relates to a method for preparing a MOF shaped body in the form of spheres, MOF shaped bodies in the form of spheres and a method of uptake of at least one substance for the purposes of its storage, separation, controlled release, chemical reaction or as support utilizing MOF shaped bodies in the form of spheres.

Abstract: A catalytic additive comprising an intermediate pore zeolite, such as ZSM-5 is treated so as to improve propylene yields when the additive is included in a FCC catalytic inventory by first treating the zeolite with a phosphorus compound to incorporate the phosphorus in the zeolite, and mixing the P-treated zeolite with a matrix component comprising kaolin and another phosphorus-containing compound.

Abstract: Hollow porous metal oxide microspheres are provided. The microspheres may be used as a support for a catalyst, particularly an exhaust treatment catalyst for an internal combustion engine. Also provided are methods of making the microspheres, methods of using the microspheres as catalyst supports, and methods of exhaust treatment using catalyst articles comprising the microspheres.

Abstract: The present invention pertains to novel core-shell particles comprising a core of iron oxide and a shell of cobalt oxide, characterized in that they are spherical with a number average diameter, as measured by TEM, of between 1 and 20 nm. This invention is also directed to their uses in the manufacture of a catalyst, and to the method for preparing these particles, by precipitating cobalt oxide onto magnetite or hematite particles which are themselves precipitated from Fe(III) and optionally Fe(II) salts.

Abstract: A high activity polyolefin catalyst system comprising titanium containing pro-catalyst component, a co-catalyst component and an external electron donor compound is provided wherein the high activity polyolefin catalyst system is having controlled morphology and less fines. At least one embodiment of the present invention is more directed to provide a method for the preparation of titanium containing pro-catalyst component from solid spherical shaped magnesium containing pro-catalyst precursor wherein the spherical morphology of the pro-catalyst precursor is maintained through out the reaction in order to achieve titanium-containing pro-catalyst having controlled morphology. The polymerization of lower olefins in the presence of high activity polyolefin catalyst having controlled morphology provides polyolefins with minimal polymer fines.

Abstract: A catalyst for hydrotreating and/or hydroconverting heavy metal-containing hydrocarbon feeds, comprises a support in the form of mainly irregular and non-spherical alumina-based agglomerates the specific shape. The catalyst is prepared by a specific order of steps: crushing, calcining, acidic autoclaving, drying, further calcining and impregnation with catalytic metals.

Abstract: Hollow conjugated polyelectrolyte (HCPE) microcapsules contain at least one conjugated polyelectrolyte and at least one other polyelectrolyte of complementary charge and the microcapsule has a hollow core. The conjugated polyelectrolyte is a polymer with a multiplicity of charged repeating units where a portion of the charged repeating units form a pi-conjugated sequence. The complementary polyelectrolyte is a polymer with a complementary charged repeating unit to the charged repeating units of the conjugated polyelectrolyte. The HCPE microcapsules can be formed by successively coating a sacrificial core with alternating layers of complementary polyelectrolytes, at least one of which is a conjugated polyelectrolyte. The sacrificial core can be removed to form the hollow center of a HCPE microcapsule.

Abstract: Provided is an alumina-based sulfur recovery catalyst as well as its preparation method, characterized in that the catalyst has a specific surface area of at least about 350 m2/g, a pore volume of at least about 0.40 ml/g, and the pore volume of pores having a pore diameter of at least 75 nm comprises at least about 30% of the pore volume. The alumina-based catalyst according to present invention is made from flashed calcined alumina, pseudoboehmite and optionally, a binder. The present invention further relates to an use of the alumina-based sulfur recovery catalyst and a method for recovering sulfur by using this catalyst.

Abstract: A method is described for preparing a molecular sieve-containing catalyst for use in a catalytic process conducted in a stirred tank reactor. The method comprises providing a mixture comprising a molecular sieve crystal and forming the mixture into catalyst particles having an average cross-sectional dimension of between about 0.01 mm and about 3.0 mm. The mixture may include a binder and the catalyst particles are then calcined to remove water therefrom and, after calcination and prior to loading the catalyst particles into a reactor for conducting the catalytic process, the catalyst particles are coated with a paraffin inert to the conditions employed in the catalytic process.

Abstract: Disclosed is an adsorptive ball for recovering precious metals and resources, a method for manufacturing the adsorptive bale, a flow through-continuous deionization (FT-CDI) module capable of recovering precious metals by using the adsorptive ball, and a flow through-continuous deionization (FT-CDI) apparatus having the flow through-continuous deionization (FT-CDI) installed thereat.

Abstract: Adducts comprising a MgCl2, an alcohol ROH in which R is a Cl—ClO hydrocarbon group, present in a molar ratio with MgCl2 ranging from 0.5 to 5 and less than 15% wt, based on the total weight of the adduct, of a metal salt of an aliphatic carboxylic acid having from 8 to 22 carbon atoms.

Abstract: The present invention relates to spherical beads comprising at least one metal and/or semimetal oxide, having a mean diameter in the range from 10 to 120 ?m, a BET surface area in the range from 400 to 800 m2/g and a pore volume in the range from 0.3 to 3.0 cm3/g, wherein the diameter of a given bead at any one point of said bead deviates by less than 10% from the average diameter of said bead and the surface of said bead is substantially smooth, and also to a process for producing these spherical beads, to a particulate catalyst comprising the spherical beads and to the use of the spherical beads as catalysts or catalyst carriers.

Abstract: A process for the preparation of a promoted VPO catalyst, wherein the catalyst comprises the mixed oxides of vanadium and phosphorus and wherein the catalyst is promoted with at least one of niobium, cobalt, iron, zinc, molybdenum or titanium, said process comprising the steps of (i) preparing a VPO catalyst comprising vanadyl pyrophosphate as the major component and containing less than 5 wt % of vanadyl phosphate, (ii) contacting the VPO catalyst with a solution comprising a metal source compound of at least one metal selected from the group consisting of niobium, cobalt, iron, zinc, molybdenum or titanium to form a metal impregnated VPO catalyst, and (iii) drying the metal impregnated VPO catalyst to form the promoted VPO catalyst. In one embodiment, a niobium promoted VPO catalyst is prepared.

Abstract: A semi-continuous process and system thereof, for the synthesis of a narrow particle size distribution Zeigler Natta procatalyst for use in the manufacture of polyolefins. The process comprises: (a) mixing a reaction mixture containing a titanium compound; (b) charging a first reactor with said reaction mixture; (c) removing excess reactants from said first reactor as a filtrate; (d) feeding said filtrate to at least one further reactor; and continuously removing excess reactants from said at least further reactor.

Abstract: Process for hydrogenating organic compounds in the gas phase in the presence of a catalyst comprising a nanoparticulate palladium cluster and a gas- and liquid-permeable shell comprising zirconium oxide.

Abstract: The invention relates to mixed oxide catalysts made of hollow shapes for the catalytic gas phase oxidation of olefins, and to a method for producing the catalysts by applying them as a layer to a carrier made of organic material and removing said organic material. The reaction into aldehydes and carboxylic acids occurs by air or oxygen in the presence of inert gases in different quantity ratios, at elevated temperatures and pressure in the presence of said catalysts.

Abstract: A spheric magnesium compound comprises a reaction product of at least the following components: (a) a magnesium halide having a formula of MgX2-nRn, wherein X is independently chloride or bromide, R is a C1-C14 alkyl, a C6-C14 aryl, a C1-C14 alkoxy, or a C6-C14 aryloxy, and n is 0 or 1; (b) an alcohol compound; and (c) an epoxy compound having a general formula (1), wherein R2 and R3 are independently hydrogen, a C1-C5 linear or branched alkyl, or a C1-C5 linear or branched haloalkyl. The magnesium compound has characteristic DSC curve and X-ray diffraction pattern, and can be used as a carrier for olefin polymerization catalyst. stereoregularity of polymer having high melt index, and low content of polymer fines.

Abstract: A process for producing geometric shaped catalyst bodies K whose active material is a multielement oxide of stoichiometry [BiaZ1bOx]p[BicMo12FedZ2eZ3fZ4gZ5hZ6iOy]1, in which a finely divided oxide BiaZ1bOx and, formed from element sources, a finely divided mixture of stoichiometry BicMo12FedZ2eZ3fZ4gZ5hZ6i are mixed in a ratio of p:1, this mixture is used to form shaped bodies and these are treated thermally, where 0<c?0.8.

Abstract: Process for the selective oxidation of ethane to ethylene and/or acetic acid, and/or the selective oxidation of ethylene to acetic acid, by contacting ethane and/or ethylene with a molecular oxygen-containing gas at elevated temperature in the presence of a spray-dried supported catalyst composition. The supported catalyst composition includes molybdenum, vanadium and niobium metal components, supported on a support comprising alpha-alumina. The supported catalyst is prepared by forming a slurry of the metal components and alpha-alumina support particles or an alpha-alumina support precursor, and spray-drying the slurry.

Abstract: The present invention relates to a high-strength silicoaluminophasphate-34 (SAPO-34) microsphere catalyst, a method for preparing the same, and a method for preparing light olefins by using the same, and when described in more detail, the present invention relates to a method for preparing a SAPO-34 microsphere catalyst, including: spray drying a mixed slurry including a matrix, a binder, an additive, and the like to a SAPO-34 slurry prepared by a hydrothermal synthesizing method using various organic templates such as tetraethylammonium hydroxide (TEAOH), and the like alone or in mixtures to prepare microspheres, and firing the microspheres, and to a SAPO-34 microsphere catalyst for a circulating-fluidized bed reactor, prepared by the preparation method. The SAPO-34 microsphere catalyst of the present invention has excellent reaction activity while having high strength, and thus is appropriate for use in a circulating-fluidized bed reactor requiring high strength of the catalyst.

Abstract: Disclosed are a nanocrater catalyst in metal nanoparticles with a nanocrater form of hole structure in center of the catalyst which is useful for manufacturing nano-sized materials and/or articles with desired structure and characteristics, a preparation method thereof including a plasma etching and chemical etching process (“PTCE process”), and nano-sized materials and/or articles manufactured by using the nanocrater catalyst in metal nanoparticles.

Abstract: The present invention provides a sol of spinous silica-based particles in which silica-based particles having peculiar forms, spinous forms are dispersed in a solvent. The spinous silica-based particles have verrucous projections formed on surfaces of spherical silica-based particles. In the spinous particles, a value of the surface roughness (SA1/SA2, SA1 indicating a specific surface area measured by the BET method or the Sears method and SA2 indicating a specific surface area converted from an average particle diameter (D2) measured by the image analysis method) is in the range from 1.7 to 10. Furthermore the average diameter (D2) measured by the image analysis method is in the range from 7 to 150 nm.

Abstract: The present invention relates to spherical beads comprising at least one metal and/or semimetal oxide, having a mean diameter in the range from 10 to 120 ?m, a BET surface area in the range from 400 to 800 m2/g and a pore volume in the range from 0.3 to 3.0 cm3/g, wherein the diameter of a given bead at any one point of said bead deviates by less than 10% from the average diameter of said bead and the surface of said bead is substantially smooth, and also to a process for producing these spherical beads, to a particulate catalyst comprising the spherical beads and to the use of the spherical beads as catalysts or catalyst carriers.

Abstract: A process for introducing annular coated catalysts K into a reaction tube of a tube bundle reactor, in which adhering pairs of annular coated catalysts K formed in the preparation of the annular coated catalysts K, before the introduction thereof into the reaction tube, are removed at least partly from the annular coated catalysts K.

Abstract: Thermally stable catalyst for heterogeneously catalyzed oxidation in the presence of hydrogen chloride and/or chlorine, comprising nanoparticulate core of a ruthenium compound with surrounding gas- and liquid-pervious shell of zirconium oxide or titanium oxide.

Abstract: A catalyst, useful in the preparation of isoolefins and containing 0.1 to 20% by mass of an alkali metal oxide, an alkaline earth metal oxide and mixtures thereof; 0.1 to 99% by mass of aluminum oxide; and 0.1 to 99% by mass of silicon dioxide, is prepared by a) treating an aluminosilicate with an aqueous alkali metal salt solution, an alkaline earth metal salt solution and mixtures thereof, under acidic conditions, to obtain a treated aluminosilicate; and b) calcining the treated aluminosilicate, to obtain the catalyst.

Abstract: A catalyst and process for hydrotreating and/or hydroconverting heavy metal-containing hydrocarbon feeds, said catalyst comprising a support in the form of beads based on alumina, at least one catalytic metal or a compound of a catalytic metal from group VIB (column 6 in the new periodic table notation), optionally at least one catalytic metal or compound of a catalytic metal from group VIII (columns 8, 9 and 10 of the new periodic table notation), with a pore structure composed of a plurality of juxtaposed agglomerates, each formed by a plurality of acicular platelets, the platelets of each agglomerate being generally radially orientated with respect to each other and with respect to the center of the agglomerate. The catalyst also comprises at least one doping element selected from the group constituted by phosphorus, boron, silicon (or silica which does not belong to that which could be contained in the selected support) and halogens.