摘要:
A method for preparing a suspension of LDH particles comprises the steps of preparing LDH precipitates by coprecipitation to form a mixture of LDH precipitates and solution; separating the LDH precipitates from the solution; washing the LDH precipitates to remove residual ions; mixing the LDH precipitates with water; and subjecting the mixture of LDH particles and water from step (d) to a hydrothermal treatment step by heating to a temperature of from greater than 80° C. to 150° C. for a period of about 1 hour to about 48 hours to form a well dispersed suspension of LDH particles in water.
摘要:
Composite particles of a metal oxide particle within a crosslinked, cored dendrimer are described. Additionally, methods of making the composite particles and compositions that contain the composite particles are described.
摘要:
Compositions useful for treating the exhaust gases of diesel engines contain zirconium oxide, silicon oxide and at least one oxide of at least one element M selected from among titanium, aluminum, tungsten, molybdenum, cerium, iron, tin, zinc, and manganese, in the following mass proportions of these different elements: silicon oxide: 5%-30%; M-element oxide: 1%-20%; the balance being zirconium oxide; such compositions also have an acidity, as measured by the methylbutynol test, of at least 90% and are prepared by placing a zirconium compound, a silicon compound, at least one M-element compound and a basic compound in a liquid medium, thereby generating a precipitate, maturing the precipitate in a liquid medium and separating and calcining the precipitate.
摘要:
There is provided a colloidal particle of an oxide of at least one metal selected from the group consisting of Ti, Fe, Zr, Sn, Ta, Nb, Y, Mo, W, Pb, In, Bi, and Sr, which is capable of being dispersed in a hydrophobic organic solvent, and a hydrophilic organic solvent dispersed sol thereof or a sol thereof dispersed in a hydrophobic organic solvent having a solubility of water of 0.05 to 12% by mass, and further, a fine powder of a metal oxide colloidal particle capable of being redispersed in various organic solvents. A silane treated modified metal oxide colloidal particle on the surface of which an amine compound and 1 to 4 silyl group(s) per 1 nm2 of the surface area are bonded, and which is produced by coating a metal oxide colloidal particle as a core with a complex oxide colloidal particle.
摘要:
The present invention is directed to a method of making metal oxide and mixed metal oxide particles. The method includes treating a mixture formed from a metal source, such as metal alkoxide, a surfactant, and a first alcohol in an aqueous media at a very high metal oxide yield. The mixture is reacted using a catalyst to form metal oxide particles having a desired particle size in said mixture. The method is particularly suitable for forming silica particles. The metal oxide particles can then be heat treated to form synthetic fused metal oxides such as, for example, synthetic fused silica.
摘要:
A procedure for obtaining mixed multimetallic oxides derived from hydrotalcite type compounds, characterized in that the laminar metallic hydroxides obtained are constituted by three or four metallic cations, forming part of the sheets of the hydrotalcite type material represented by the formula: [M(II)1−x−y−zM(II)′xM(III)yM(III)′z(OH)2](An−y+z/n).mH2O. by a process comprising: (1) preparing an aqueous or organic solution containing three or more cations; (2) preparing an alkaline solution; (3) slowly combining solutions (1) and (2) to cause the co-precipitation of the cations in the form of hydroxides; (4) washing the precipitate containing the hydrotalcites with water, until removal of the non-precipitated ions; (5) drying; and (6) calcining the hydrotalcites.
摘要:
A mesoporous oxide composition includes, other than oxygen, a major amount of aluminum and lesser amounts of phosphorus and at least one rare earth element. The compositions have high surface area and excellent thermal and hydrothermal stability, with a relatively narrow pore size distribution in the mesoporous range. These compositions may be prepared by a hydrothermal co-precipitation method using an organic templating agent. These mesoporous oxide compositions may be used as catalysts or as supports for catalysts, for example, in a fluid catalytic cracking process.
摘要:
A procedure for obtaining mixed multimetallic oxides derived from hydrotalcite type compounds, characterized in that the laminar metallic hydroxides obtained are constituted by three or four metallic cations, forming part of the sheets of the hydrotalcite type material represented by the formula: [M(II)1−x−y−zM(II)′xM(III)yM(III)′z(OH)2](An−y+z/n).mH2O. by a process comprising: (1) preparing an aqueous or organic solution containing three or more cations; (2) preparing an alkaline solution; (3) slowly combining solutions (1) and (2) to cause the co-precipitation of the cations in the form of hydroxides; (4) washing the precipitate containing the hydrotalcites with water, until removal of the non-precipitated ions; (5) drying; and (6) calcining the hydrotalcites.
摘要:
Wet-chemical methods involving the use of water-soluble hydrolytically stable metal-ion chelate precursors and the use of a nonmetal-ion-containing strong base can be used in a coprecipitation procedure for the preparation of ceramic powders. Examples of the precipitants used include tetraalkylammonium hydroxides. A composition-modified barium titanate is one of the ceramic powders that can be produced. Certain metal-ion chelates can be prepared from 2-hydroxypropanoic acid and ammonium hydroxide.
摘要:
A reactor for the wet-chemical co-precipitation of oxide powders includes a cylindrical structure having first and second ends and a lumen extending the length of the tube. A central axis extends through the lumen. The first end is closed. The reactor also includes a first inlet port disposed proximal to the first end of the cylindrical structure and providing access through the cylindrical structure to inject a first reactant solution. The reactor further includes a second inlet port disposed proximal to the first end of the cylindrical structure and providing access through the cylindrical structure to inject a second reactant solution. The first and second inlet ports are disposed on opposite sides of the cylindrical structure and are coaxial relative to the central axis.