Preparation method of ultrahigh-purity and superfine aluminium oxide powder

Abstract

The invention relates to a preparation method of ultrahigh-purity and superfine alumina powder. The preparation method comprises the following process steps of: (1) injecting a high-purity aluminium sheet, isopropanol and a catalyst into a synthetic reaction tower to generate gaseous aluminium isopropoxide; cooling gaseous aluminium isopropoxide into liquid aluminium isopropoxide by virtue of a condenser; (2) injecting liquid aluminium isopropoxide into a reduced pressure distillation purification tank for evaporating to form steam, injecting the steam to a material receiving tank to become liquid ultrahigh-purity aluminium isopropoxide; (3) adding ultrahigh-purity aluminium isopropoxide into a vacuum stirring and drying machine, injecting high-purity water, and carrying out hydrolysis reaction under the circulating water cooling condition, so as to obtain ultrahigh-purity aluminium hydroxide and isopropanol aqueous solution; and drying in a vacuum stirring and drying machine; and (4) placing ultrahigh-purity aluminium hydroxide powder into a corundum crucible, and calcining in an electrically pushed slab kiln until the aluminium hydroxide powder is changed into alpha-Al2O3 powder, thus preparation is completed.

Description

technical field [0001] The invention relates to a method for preparing high-purity alumina powder by using a high-purity aluminum ingot with a purity >99.99%, and is particularly suitable for preparing an alumina powder with an alumina content of ≥99.999% and an average primary particle diameter of 0.2-0.4 μm. Background technique [0002] At present, the methods for preparing high-purity alumina powder include aluminum ammonium sulfate thermal decomposition method, aluminum ammonium carbonate thermal decomposition method, Bayer improved method, spark discharge method in aluminum powder water, organic aluminum decomposition method, choline method, etc. Among them, the aluminum alkoxide hydrolysis method is currently the most advanced method for preparing high-purity, ultra-fine alumina. The aluminum alkoxide hydrolysis method is a new method of producing inorganic materials using organic chemical methods. It is very different from the traditional production method. A larg...

AI Technical Summary

Problems solved by technology

The aluminum alkoxide hydrolysis method is a new method of producing inorganic materials using organic chemical methods. It is very different from the traditional production method. A large amount of organic solvent isopropanol is used as a raw material. Therefore, the production process has strict safety requirements and is very important for fire and explosion protection. There are strict requirements, all equipment must have fire and explosion-proof functions, and strict evaluation of the surrounding environment is also required. The manufacturer must have relevant qualifications, the equipment design and manufacturing unit, and the pressure vessel manufacturing unit must have relevant qualifications, so the investment in equipment is relatively large.

However, product testing equipment and instruments are expensive, and testing personnel are required to have a high degree of education, so the cost is also very high