摘要:
Disclosed is alumina powder having a relative standard deviation of a volume-based crystallite diameter distribution of 0.25 to 0.80, as determined by analyzing an X-ray diffraction peak by a fundamental parameter method.
摘要:
The present disclosure provides a microsphere of oxide in the shape of raspberry, an FT synthesis catalyst containing the same as a support, and their preparation methods and applications. The inventive microsphere of oxide in the shape of raspberry is a hollow microsphere with a large hole on the surface, wherein the hollow microsphere has a hollow structure inside, and the large hole and the hollow structure are connected to form a cavity with an open end, wherein the oxide in the microsphere of oxide in the shape of raspberry is one or more selected from the group consisting of alumina, silica, zirconia, magnesium oxide, calcium oxide and titania. The inventive microsphere of oxide in the shape of raspberry shows better mass and heat transfer characteristics, and has strength which is significantly higher than that of existing products with similar structures. The microsphere of oxide in the shape of raspberry can be prepared by using the oxide and/or a precursor thereof as raw materials. The preparation is simple, low in cost, high in efficiency and suitable for large-scale industrial applications. The inventive FT synthesis catalyst comprises a microsphere of oxide in the shape of raspberry as a support and an active metal component supported on the support, wherein the active metal component is one or more selected from the group consisting of Co, Fe, and Ru. The inventive FT synthesis catalyst solves the diffusion problem in FT synthesis reaction and improves FT synthetic performance.
摘要:
The present invention relates to a method for the production of aluminum oxide particles of spherical morphology and with a particles size in the submicron range.
摘要:
A novel solution route has been developed that after heat-treatment to 500-600° C. under inert atmosphere, yields highly porous composites of nano-sized metal (Ni) particle inclusions in ceramics (Al2O3). Metal loadings could be made from 95% Ni. The metal inclusion sizes in the Ni—Al2O3 system with the 10 atom % Ni sample were 4-7 nm, while for the 75 atom % Ni sample they were 5-8 nm. It was shown that the 10 atom % Ni sample could be used as a catalyst for the conversion of CO2 and CH4 in the temperature range 550-700° C., while higher temperatures led to growth of the Ni particles and carbon poisoning over time. The solution routes could also be deposited as thin dense films containing
摘要:
The present invention relates to a system for optimizing and controlling the particle size distribution and scale-up of production of nanoparticle in an aerosol flame reactor. The method provides nanoparticles with desired, optimized and controlled particle size and the specific surface area in aerosol reactors using a simulation tool with programmed instructions. The said simulation tool couples flame dynamics model and particle population balance model.
摘要:
The present invention is a process for the conversion of aluminum oxide hydroxide (AlOOH) to aluminum oxide. 30 to 70 wt-% of AlOOH, 30 to 70 wt % ammonium hydrogencarbonate NH 4 HCO 3 and 0 to 20 wt-% water are combined to produce a mixture. This mixture is then cured at a temperature from 30° to 90° C to convert at least 5% of the AlOOH to a ammonium hydroxycarbonate (dawsonite - type) intermediate and then the dawsonite-type intermediate is decomposed at a temperature from 130° to 320° C to produce aluminum oxide. The aluminum oxide can be further calcined at 500° to 800° C to produce a gamma-theta phase alumina.