36results about How to "High crystal phase purity" patented technology

The invention provides a method for preparing multiaperture spherical magnetic ferrite (zinc ferrite, nickel ferrite, cobalt ferrite and manganese ferrite) by taking dodecylamine as a precipitator by a solvothermal method. The preparation method is characterized in that an ethylene glycol solution of ferric trichloride and chloride is used as a reaction solution; dodecylamine is used as the precipitator; and the ethylene glycol solution and the dodecylamine are stirred and mixed uniformly at the room temperature to form a liquid phase reaction solution; and the liquid phase reaction solution is transferred to a reaction kettle for hydrothermal reaction at 180-250 DEG C. Products are separated, washed and dried to obtain corresponding multiaperture ferrite powder after reaction. The preparation method has the characteristics of being low in raw materials, simple in process, convenient in operation, controllable in shape, and the like.

The invention provides a method for preparing calcium carbonate with controllable topography by taking calcium sulphate as calcium resource, and the topography of calcium carbonate comprises fusiformis, sphere, rod shape and the like. The invention is characterized in that calcium sulphate which is slightly soluble to water is dispersed in N, N-dimethyl formamide or absolute ethyl alcohol to form suspension solution; carbonate solution is added to react for certain time to decentralize and separate products; after the product is dispersed to deionized water to be stirred for certain time, the product is decentralized, washed and dried to obtain single-phase calcium carbonate powder. The topography of the product can be controlled by changing preparation conditions, such as reaction temperature, reaction time, reactant density and dissolved solvent and the like. The method has the characteristics of cheap raw material, simple technology, simple operation, controllable topography and the like.

The present invention is artificial pure diopside crystal material and its preparation process. The artificial diopside crystal material is prepared with silica sand, tail pyrite, kaolin, albite, limestone and other mineral materials, and through the technological steps of compounding material, smelting, forming, annealing, coring, crystallization, etc. Chemically, the materials consist of SiO2 47-61 wt%, Al2O3 4-9 wt%, CaO 12-20 wt%, MgO 4-7 wt%, TiO2 2-15 wt%, NaO2+KO2 3-7 wt%, ZrO2 1-4 wt%, ZnO 0-4 wt%, P2O5 1-4 wt%, F 1-3 wt% and C 1-3 wt%. The artificial pure diopside crystal material consists of micron level crystal grains, and has high compactness, high mechanical performance, high wear resistance, high corrosion resistance, excellent impact performance, no radioactivity and other features.

The invention discloses a preparation method for improving the thermal stability of magnesium-aluminum hydrotalcite. The preparation method comprises the following steps: using magnesium hydroxide andalpha-phase aluminum hydroxide products as raw materials, carrying out acid dissolution-ball milling-alkali precipitation-crystallization process flow to prepare the magnesium-aluminum hydrotalcite product with high thermal stability. Aiming at the problem that a large amount of salt-containing wastewater is generated in the production process due to the fact that soluble magnesium salt/aluminumsalt is used as a raw material in a traditional process, a magnesium source/aluminum source is innovatively improved, a production technology combining a physical method and a chemical method is designed, and the prepared magnesium-aluminum hydrotalcite product has the advantages of being high in thermal stability, good in dispersity and the like.

The invention provides haze-reduction paint for building wall surfaces and a preparation method. The method includes the steps: firstly, preparing pseudo-boehmite sol coated tourmaline loaded zinc oxide nano-crystalline composite spherical fine particles to serve as photocatalysts; secondly, preparing slurry from the particles, nano-silicon dioxide, nano-wollastonite, super-fine talcum powder, defoaming agents, dispersing agents, coalescing agents, preservatives and water; finally, matching the slurry, organosilicone acrylic resin and thickening agents to form the haze-reduction paint for thebuilding wall surfaces. By the aid of a pseudo-boehmite sol coated tourmaline loaded zinc oxide nano-crystalline composite material with the advantages of large specific surface, high pore volume andthe like, outward flow of catalytic active matters is avoided, the haze-reduction paint is provided with a adsorbent with excellent performance, the paint and the zinc oxide nano-crystalline are compound, high adsorption capacity of the adsorbent and visible light drive photocatalysis to degrade cationic organic pollutants, air quality is improved, the paint has remarkable effects on control of large-area haze, and further, and the paint is simple in preparation process, low in raw material cost and suitable for large-scale popularization.

The invention discloses a preparation method of a carbon-coated LiVPO4F positive electrode material. The preparation method comprises the following steps: adding oxalic acid, citric acid or ascorbic acid into deionized water to form a transparent solution, sequentially adding a vanadium source, a lithium source, a phosphorus source and a fluorine source according to the molar ratio of 1:1:1:1 at the temperature of 20-90 DEG C, conducting uniform mixing in the solution, conducting reacting for 1-12h to form a colloidal solution, and conducting drying at the temperature of 70-140 DEG C for 6-48hto obtain a solid product; carrying out heat treatment on the dried solid product in an inert atmosphere at the temperature of 300-500 DEG C for 1-12h to obtain an intermediate product; and mixing the intermediate product with a fluorine-containing polymer (PTFE, PVDF or PCTFE) accounting for 5%-100% of the mass of the intermediate product, carrying out ball milling for 1-24 hours, and conductingsintering in an inert atmosphere at the temperature of 500-800 DEG C for 1-12 hours to obtain the pure-phase LiVPO4F/C positive electrode material. The carbon-coated LiVPO4F material prepared by theinvention has high crystalline phase purity, and the introduction of the fluorine-containing polymer not only can be used as an additional fluorine source to effectively improve the crystalline phasepurity of the material, but also can be used as a carbon source to coat the surface of LiVPO4F to improve the electron conductivity of the material, thereby obtaining excellent electrochemical properties.

The invention relates to the technical field of piezoelectric catalytic hydrogen production materials, and provides a tin and cerium-strontium titanate solid solution piezoelectric hydrogen production catalyst as well as a preparation method and application thereof. The chemical general formula of the material prepared according to the invention is SnxCeySr(1-x-y)TiO3 (x is more than 0 and less than or equal to 0.15, and y is more than 0 and less than or equal to 0.15). A Sr source, a Ce source, a Sn source and a Ti source are mixed with water and ethylene glycol, a coprecipitation method is adopted, a precursor of the tin and cerium-strontium titanate solid solution piezoelectric hydrogen production catalyst is prepared, and finally the solid solution piezoelectric hydrogen production catalyst is formed through high-temperature calcination. The result of the embodiment shows that the piezoelectric hydrogen production performance of SrTiO3 is greatly improved due to the introduction of Sn and Ce. Moreover, when x is equal to 0.1 and y is equal to 0.1, the hydrogen production efficiency is the best, reaches 411 [mu]mol/g and is far higher than 53.45 [mu]mol/g of SrTiO3.