摘要:
A continuous process and apparatus for the production of at least approximately spherical, substantially solid particles, in which the particles are granulated in a circulating fluidized bed. This can be achieved by spraying a suspension or a solution of the solid which forms the particles into a chamber. A drying gas is passed through the chamber at a velocity which is sufficient to effect pneumatic conveying of already partially dried or agglomerated particles. The particles conveyed by the drying gas stream are separated from the exhaust gas stream and returned, at least in part, to the chamber. Particles with a size within the desired particle size range are continuously discharged from the chamber, such that the mass present in the chamber remains constant.
摘要:
The present invention relates to spherical solid catalyst components for the polymerization of olefins, comprising a titanium compound, supported on a magnesium halide, containing more than one Ti-halogen link and optionally containing groups different from halogen in an amount lower than 0.5 mole per mole of Ti. Spherical solid compounds of the invention are characterized by having a surface area, measured by the BET method, of lower than 70 m2/g, a total porosity, measured by the mercurium method, higher than 0.5 cm3/g and a pore radius such that at least 50% have values higher than 800 null.
摘要:
A process for producing inorganic spheres, which comprises injecting an aqueous liquid containing an inorganic compound into a laminar flow of an organic liquid which runs at a flow rate of from 0.001 to 2 m/s in a flow path compartmentalized by a partition wall through a plurality of inlet holes formed in one partition wall to form a W/O type emulsion containing the organic liquid as a dispersion medium and the aqueous liquid containing the inorganic compound as a dispersed phase, and solidifying the aqueous liquid containing an inorganic compound in the W/O type emulsion, wherein the partition wall having a plurality of inlet holes is made of a metal sheet having a surface subjected to water repellent treatment.
摘要:
A process for the preparation of a fluid bed vinyl acetate (VAM) catalyst comprising impregnating a support comprising a mixture of substantially inert microspheroidal particles with a solution comprising a metal salt of Pd and M, wherein M comprises Ba, Cd, Au, La, Nb, Ce, Zn, Pb, Ca, Sr, Sb or mixtures thereof, reducing the metal salts to form a deposit of Pd and M on the support surface and impregnating the support with at least one alkali metal salt. At least 50% of the particles used for the microspheroidal support have a particle size below 105 microns.
摘要:
Disclosed is a method for extending the life of dehydrogenation catalysts used to prepare vinyl aromatic hydrocarbons. The catalysts, which typically include both iron oxide and potassium containing catalysis promoter, are exposed to additional potassium delivered using a potassium carboxylate. The potassium carboxylates are desirably free of halogens and other catalysts poisons or groups that could result in the undesirable properties in vinyl aromatic hydrocarbons produced therewith. The present invention is particularly useful with the production of styrene and methyl styrene.
摘要:
The present invention teaches the use of particular soluble metallocene catalysts to produce stereoregular polymers in gas phase polymerizations wherein the catalysts are fed into a particle lean zone in the reactor. The metallocenes catalysts are bridged bis-(substituted indenyl) compounds.
摘要:
A method for producing small spherical particles that are especially useful as catalysts and catalyst supports employed in chemical processes is disclosed. According to some embodiments, the method includes impregnating a porous support with a metal or metal oxide and dissolving the support to release spherical particles. In certain embodiments the support that is employed in the method comprises a number of spherical voids which determine the size of the spherical particles, and preferably have micrometer range diameters. One embodiment of an attrition resistant Fischer-Tropsch catalyst comprises a plurality of micrometer size spherical metal and/or metal oxide particles that are prepared according to the above-described method.
摘要:
The present invention provides a process for producing spherical catalyst carrier of silica, silica-alumina composition, zirconia-alumina composition, titania-alumina composition, boria-alumina composition, or boria-silica-alumina composition which has almost the same pore characteristics as alumina hydrate gel, silica-alumina hydrate gel, zirconia-alumina hydrate gel, or titania-alumina hydrate gel (or alumina hydrate paste, boria-alumina hydrate paste, or boria-silica-alumina hydrate paste) as the major raw material, has uniform sphericity and smooth surface and homogeneity, and has a macropore volume that can be controlled. The process comprises adding a polysaccharide solution to any of alumina, silica-alumina, zirconia-alumina, or titania-alumina in the form of hydrate gel, or alumina, boria-alumina, or boria-silica-alumina in the form of hydrate paste, mixing them to form a slurry with a controlled concentration, dropping the slurry into a solution containing multivalent metal ions, thereby forming spherical hydrogel, and performing the additional steps of aging, washing, drying, and calcining.