Freeze forming preparation process of ternary lithium ceramic microphere

Abstract

The invention provides a method for preparing ternary lithium ceramic microspheres by freeze molding, which is characterized in that: mixing the reactant raw materials of ternary lithium ceramic microspheres or ceramic powder with a polymer binder and a solvent, and mixing them in a ball mill Mix evenly to form a suspension slurry, and perform defoaming treatment. The slurry after defoaming treatment is transferred to the microsphere forming device, and the slurry is dropped into the low-temperature cooling medium through the microsphere forming device. During the movement of the droplets, microspheres are formed due to the surface tension, and the microspheres enter the low-temperature cooling medium. The spherical shape can be maintained by rapid cooling, and the ceramic microsphere precursor is formed by low-temperature vacuum drying in a freeze dryer. The microsphere green body undergoes multi-step program-controlled temperature-controlled heat treatment of calcination, calcination and sintering, and finally forms ternary lithium ceramic microspheres. Ceramic microspheres have good sphericity, controllable particle size, good particle size dispersion, high apparent density, high phase purity, and high breaking strength. The preparation method of the invention has the characteristics of simple process and low cost, and is easy to expand to large-scale production.

Description

Technical field [0001] The invention belongs to the technical field of preparation of porous ceramic microspheres, and specifically relates to a method for preparing ternary lithium ceramic microspheres by freezing and forming. Background technique [0002] In order to solve the world's energy shortage problem, various countries regard research as one of the effective ways to develop new energy and solve the energy crisis. The fuel tritium needed in thermonuclear fusion reactors is generally through 6 Li (n, α) T reaction to achieve. In order to realize the fuel cycle, the reactor must be “self-sustaining” of tritium. To this end, it is necessary to add a lithium-containing tritium breeder to the cladding, and use the neutrons produced by the core DT reaction to react with the lithium-containing materials in the breeder cladding. Tritium is produced to realize tritium proliferation. [0003] As a solid tritium ceramic material (tritium multiplier), lithium ceramic has the charact...

AI Technical Summary

Problems solved by technology

Among them, the melt-spray method can produce high-density lithium ceramic microspheres, but the defect of this method is that it uses an expensive platinum-rhodium alloy furnace

When using the traditional wet method to prepare lithium ceramic microspheres, since the gel solid content of the microsphere precursor is difficult to exceed 50%, the density of the final formed lithium ceramic microspheres is difficult to be higher than 90% T.D. (theoretical density)

[0005] Most of the existing ceramic microsphere preparation methods need to pre-prepare the ceramic powder of the ternary lithium compound, and then generate ceramic microspheres. The sphericity of the ceramic microspheres is not good, the internal pore structure is not rich enough, and the particle size of the microspheres is difficult to control. Poor particle size dispersion

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