Patent classifications
C04B38/0645
Batch compositions comprising pre-reacted inorganic particles and methods of manufacture of green bodies therefrom
Batch compositions containing pre-reacted inorganic spheroidal particles, small amount of fine inorganic particles (“fines”), and an extremely large amount of liquid vehicle. The batch compositions contain pre-reacted inorganic particles having a particle size distribution with 20 μm≤D50≤100 μm, D90≤100 μm, and D5≥10 μm; less than 20 wt % of fine inorganic particles (fines) whose particle distribution(s) have a median diameter of less than 5 μm; and a liquid vehicle in a weight percent (LV %≥28%) by super-addition to all inorganic particles in the batch composition. Fast extruding batch compositions having extremely high Tau Y/Beta ratios are provided. Green bodies, such as green honeycomb bodies and methods of manufacturing green honeycomb bodies are provided, as are other aspects.
Batch compositions comprising pre-reacted inorganic particles and methods of manufacture of green bodies therefrom
Batch compositions containing pre-reacted inorganic spheroidal particles, small amount of fine inorganic particles (“fines”), and an extremely large amount of liquid vehicle. The batch compositions contain pre-reacted inorganic particles having a particle size distribution with 20 μm≤D50≤100 μm, D90≤100 μm, and D5≥10 μm; less than 20 wt % of fine inorganic particles (fines) whose particle distribution(s) have a median diameter of less than 5 μm; and a liquid vehicle in a weight percent (LV %≥28%) by super-addition to all inorganic particles in the batch composition. Fast extruding batch compositions having extremely high Tau Y/Beta ratios are provided. Green bodies, such as green honeycomb bodies and methods of manufacturing green honeycomb bodies are provided, as are other aspects.
METHOD FOR PRODUCING METAL MATRIX COMPOSITE AND METHOD FOR PREPARING PREFORM
The present invention relates to a technique of dramatically improving a method for causing a molten metal of an Al alloy or the like to infiltrate without pressurization into a preform obtained by molding and hardening a ceramic powder, and obtaining “a metal matrix composite formed from a ceramic powder and an Al alloy or the like” in a uniform state as a whole more simply and stably, and the present invention provides “a production method for producing a metal matrix composite containing aluminum and ceramic, the method including: obtaining a mixed body by performing molding using a mixture containing a magnesium-containing powder, a ceramic powder, and an inorganic or organic/inorganic binder that is hardened when heated to 500° C. or lower; preparing a preform by calcining the mixed body at a temperature of 500° C. or lower; and causing an Al alloy or the like to infiltrate without pressurization into the obtained preform to produce the metal matrix composite containing aluminum and ceramic, and a method for preparing the preform.”
METHOD FOR PRODUCING METAL MATRIX COMPOSITE AND METHOD FOR PREPARING PREFORM
The present invention relates to a technique of dramatically improving a method for causing a molten metal of an Al alloy or the like to infiltrate without pressurization into a preform obtained by molding and hardening a ceramic powder, and obtaining “a metal matrix composite formed from a ceramic powder and an Al alloy or the like” in a uniform state as a whole more simply and stably, and the present invention provides “a production method for producing a metal matrix composite containing aluminum and ceramic, the method including: obtaining a mixed body by performing molding using a mixture containing a magnesium-containing powder, a ceramic powder, and an inorganic or organic/inorganic binder that is hardened when heated to 500° C. or lower; preparing a preform by calcining the mixed body at a temperature of 500° C. or lower; and causing an Al alloy or the like to infiltrate without pressurization into the obtained preform to produce the metal matrix composite containing aluminum and ceramic, and a method for preparing the preform.”
TABLETED ALPHA-ALUMINA CATALYST SUPPORT
A tableted catalyst support, characterized by an alpha-alumina content of at least 85 wt.-%, a pore volume of at least 0.40 mL/g, as determined by mercury porosimetry, and a BET surface area of 0.5 to 5.0 m.sup.2/g. The tableted catalyst support is an alpha-alumina catalyst support obtained with high geometrical precision and displaying a high overall pore volume, thus allowing for impregnation with a high amount of silver, while exhibiting a surface area sufficiently large so as to provide optimal dispersion of catalytically active species, in particular metal species. The invention further provides a process for producing a tableted alpha-alumina catalyst support, which comprises i) forming a free-flowing feed mixture comprising, based on inorganic solids content, at least 50 wt.-% of a transition alumina; ii) tableting the free-flowing feed mixture to obtain a compacted body; and iii) heat treating the compacted body at a temperature of at least 1100° C., preferably at least 1300° C., more preferably at least 1400° C., in particular at least 1450° C., to obtain the tableted alpha-alumina catalyst support. The invention moreover relates to a compacted body obtained by tableting a free-flowing feed mixture which comprises, based on inorganic solids content, at least 50 wt.-% of a transition alumina having a loose bulk density of at most 600 g/L, a pore volume of at least 0.6 mL/g, as determined, and a median pore diameter of at least 15 nm. The invention moreover relates to a shaped catalyst body for producing ethylene oxide by gas-phase oxidation of ethylene, comprising at least 15 wt.-% of silver, relative to the total weight of the catalyst, deposited on the tableted alpha-alumina catalyst support. The invention moreover relates to a process for producing ethylene oxide by gas-phase oxidation of ethylene, comprising reacting ethylene and oxygen in the presence of the shaped catalyst body.
TABLETED ALPHA-ALUMINA CATALYST SUPPORT
A tableted catalyst support, characterized by an alpha-alumina content of at least 85 wt.-%, a pore volume of at least 0.40 mL/g, as determined by mercury porosimetry, and a BET surface area of 0.5 to 5.0 m.sup.2/g. The tableted catalyst support is an alpha-alumina catalyst support obtained with high geometrical precision and displaying a high overall pore volume, thus allowing for impregnation with a high amount of silver, while exhibiting a surface area sufficiently large so as to provide optimal dispersion of catalytically active species, in particular metal species. The invention further provides a process for producing a tableted alpha-alumina catalyst support, which comprises i) forming a free-flowing feed mixture comprising, based on inorganic solids content, at least 50 wt.-% of a transition alumina; ii) tableting the free-flowing feed mixture to obtain a compacted body; and iii) heat treating the compacted body at a temperature of at least 1100° C., preferably at least 1300° C., more preferably at least 1400° C., in particular at least 1450° C., to obtain the tableted alpha-alumina catalyst support. The invention moreover relates to a compacted body obtained by tableting a free-flowing feed mixture which comprises, based on inorganic solids content, at least 50 wt.-% of a transition alumina having a loose bulk density of at most 600 g/L, a pore volume of at least 0.6 mL/g, as determined, and a median pore diameter of at least 15 nm. The invention moreover relates to a shaped catalyst body for producing ethylene oxide by gas-phase oxidation of ethylene, comprising at least 15 wt.-% of silver, relative to the total weight of the catalyst, deposited on the tableted alpha-alumina catalyst support. The invention moreover relates to a process for producing ethylene oxide by gas-phase oxidation of ethylene, comprising reacting ethylene and oxygen in the presence of the shaped catalyst body.
CERAMIC ARTICLES MADE FROM CERAMIC BEADS WITH OPEN POROSITY
A ceramic article and method of manufacturing. The ceramic article comprises a porous ceramic material having a microstructure comprising an interconnected network of porous spheroidal ceramic beads. The microstructure has a total open porosity defined as the sum of an open intrabead porosity of the beads and an interbead porosity defined by interstices between the beads in the interconnected network. The microstructure has a bimodal pore size distribution having an intrabead peak corresponding to the open intrabead porosity and an interbead peak corresponding to the interbead porosity. An intrabead median pore size of the intrabead porosity is less than an interbead median pore size of the interbead porosity.
CERAMIC ARTICLES MADE FROM CERAMIC BEADS WITH OPEN POROSITY
A ceramic article and method of manufacturing. The ceramic article comprises a porous ceramic material having a microstructure comprising an interconnected network of porous spheroidal ceramic beads. The microstructure has a total open porosity defined as the sum of an open intrabead porosity of the beads and an interbead porosity defined by interstices between the beads in the interconnected network. The microstructure has a bimodal pore size distribution having an intrabead peak corresponding to the open intrabead porosity and an interbead peak corresponding to the interbead porosity. An intrabead median pore size of the intrabead porosity is less than an interbead median pore size of the interbead porosity.
HIGH FILTRATION EFFICIENCY PARTICULATE FILTERS HAVING BIMODAL PORE SIZE DISTRIBUTION MADE FROM BEADS WITH OPEN POROSITY
A particulate filter and method of manufacture. The particulate filter comprises a ceramic honeycomb body comprising a plurality of intersecting walls that define a plurality of channels extending longitudinally though the ceramic honeycomb body. The intersecting walls comprise a porous ceramic material having a microstructure that comprises an interconnected network of porous spheroidal ceramic beads. The microstructure has a total porosity defined as the sum of an open intrabead porosity of the beads and an interbead porosity defined by interstices between the beads in the interconnected network. The microstructure has a bimodal pore size distribution in which an intrabead median pore size of the intrabead porosity is from 1.5 μm to 4 μm and an interbead median pore size of the interbead porosity is from 6 μm to 20 μm.
HIGH FILTRATION EFFICIENCY PARTICULATE FILTERS HAVING BIMODAL PORE SIZE DISTRIBUTION MADE FROM BEADS WITH OPEN POROSITY
A particulate filter and method of manufacture. The particulate filter comprises a ceramic honeycomb body comprising a plurality of intersecting walls that define a plurality of channels extending longitudinally though the ceramic honeycomb body. The intersecting walls comprise a porous ceramic material having a microstructure that comprises an interconnected network of porous spheroidal ceramic beads. The microstructure has a total porosity defined as the sum of an open intrabead porosity of the beads and an interbead porosity defined by interstices between the beads in the interconnected network. The microstructure has a bimodal pore size distribution in which an intrabead median pore size of the intrabead porosity is from 1.5 μm to 4 μm and an interbead median pore size of the interbead porosity is from 6 μm to 20 μm.