A method for producing a catalyst or catalyst precursor is described including: applying a slurry of a particulate catalyst compound in a carrier fluid to an additive layer manufactured support structure to form a slurry-impregnated support, and drying and optionally calcining the slurry-impregnated support to form a catalyst or catalyst precursor. The mean particle size (D50) of the particulate catalyst compound in the slurry is in the range 1-50 μm and the support structure has a porosity ≧0.02 ml/g.

A process for producing an oligomerization catalyst includes hydrothermal treatment. An oligomerization catalyst produced by the process is useful for the oligomerization of C.sub.2 to C.sub.12 olefins.

The presently claimed invention provides a layered three-way catalyst composition for purification of exhaust gases from internal combustion engines; said catalyst comprises a first layer comprising i) palladium supported on at least one alumina component and at least one oxygen storage component; and ii) barium oxide; wherein said first layer is essentially free of strontium, and a second layer comprising: i) rhodium supported on at least one zirconia component and/or alumina component; ii) strontium oxide and/or barium oxide; and iii) optionally, palladium supported on at least one alumina component. The presently claimed invention also provides a process for preparing the layered three-way catalyst composition which involves a technique such as incipient wetness impregnation technique(A); co-precipitation technique (B); or co-impregnation technique(C). The process includes preparing a first layer; preparing a second layer; and depositing the second layer on the first layer followed by calcination. The presently claimed invention further provides a a layered three-way catalytic article in which the three-way catalyst composition is deposited on a substrate in a layered fashion and its preparation.

A catalyst fibrous structure having a catalyst metal carried on a fibrous structure, wherein (a) a Log differential micropore volume distribution curve thereof obtained by measurement using a mercury intrusion technique has a peak having a maximum micropore diameter in the range of from 0.1 μm to 100 μm; (b) a Log differential micropore volume at the peak is 0.5 mL/g or more; and (c) an amount of a catalyst metal compound and a binder carried per unit volume is 0.05 g/mL or more. A production method for producing a catalyst fibrous structure having: (1) mixing a catalyst metal compound or a catalyst precursor, and an inorganic binder and a solvent; (2) grinding the mixture to obtain a coating material of the catalyst metal compound or the catalyst precursor having a median particle diameter of 2 μm or less and a viscosity of from 10 mPa.Math.s to 200 mPa.Math.s; (3) impregnating a fibrous structure with the coating material to fill up voids of the fibrous structure with the coating material of the catalyst metal compound or the catalyst precursor; (4) heating and drying the fibrous structure, directly as it is, at a temperature not lower than the boiling point of the solvent; and (5) heating and calcination the dried fibrous structure at a temperature not lower than the dehydration temperature of the inorganic binder to obtain a catalyst fibrous structure.

An alumina support for a catalyst for a gas-phase reaction that increases the catalytic activity and allows a reduction in by-product yield, and a catalyst for a gas-phase reaction that is a metal compound supported on the alumina support are provided. The alumina support for a catalyst for a gas-phase reaction has a tubular shape with at least one hollow through hole and a BET specific surface area of 140 to 280 m.sup.2/g. In this alumina support, a volume (total pore volume) of pores with a diameter of not less than 15 nm and not more than 20000 nm is 0.04 to 0.15 cm.sup.3/g, and a volume of pores with a diameter of not less than 1000 nm and not more than 20000 nm is 0.02 cm.sup.3/g or less, as measured by the mercury intrusion technique, and a tapped bulk density is 620 to 780 g/L.

In a process for producing a phosphorus-modified zeolite catalyst, an aqueous reaction mixture comprising a source of silica and a source of an organic directing agent effective to direct the synthesis of a desired zeolite is heated at a temperature and for a time sufficient to produce crystals of the desired zeolite. Wet zeolite crystals can then be separated from the reaction mixture and, without removing all the water from the wet zeolite crystals, the zeolite can be converted into the ammonium form by ion exchange, and the crystals can be treated with a phosphorus compound. The phosphorus-treated, ammonium-exchanged zeolite can then be formed into a catalyst to be heated in one or more stages to remove the water and organic directing agent from the zeolite crystals and to convert the zeolite to the hydrogen form.

The present invention provides a catalyst for the decomposition of nitrous oxide, said catalyst comprising oxides of cobalt, zinc and aluminum and an alkali metal promoter.

Provided are: a hydrotreating catalyst for hydrocarbon oil having a hydrodesulfurization activity additionally improved by: simultaneously and continuously adding an aqueous solution of an acidic compound containing titanium and an aqueous solution containing an alkaline compound to a hydrosol containing an alumina hydrate particle at a temperature of 10 to 100° C. and a pH of 4.5 to 6.5; washing the resultant to remove a contaminating ion; forming the washed product after dehydration so as to have a moisture content at which it is formable; drying the resultant; impregnating the dried product with a catalytic component aqueous solution containing at least one kind of periodic table group 6 metal compound, at least one kind of periodic table group 8-10 metal compound, at least one kind of phosphorus compound, and at least one kind of saccharide; and drying the resultant; a manufacturing method for the catalyst; and a hydrodesulfurization treatment method for hydrocarbon oil using the catalyst.

The manufacturing method of the honeycomb structure includes a raw material preparing step of adding the powder of porous silica as the inorganic pore former to a forming raw material and kneading the forming raw material to prepare the kneaded forming raw material, an extruding step of extruding the obtained forming raw material to form a honeycomb formed body, and a firing step of firing the extruded honeycomb formed body to form a honeycomb structure containing a cordierite component, and an amount of oil to be absorbed by the porous silica to be added to the forming raw material is in a range of 50 to 190 ml/100 g, and a BET specific surface area of the porous silica is in a range of 340 to 690 m.sup.2/g.

The present invention relates to spherical agglomerates based on zeolite(s) and clay(s), having controlled size and morphology, in particular a size of less than or equal to 600 μm, very good sphericity, and a high content of zeolitic material, to the process for the production thereof. These agglomerates are particularly suitable for uses in gas-phase and/or liquid-phase adsorption processes.