Application of Elemental Silicon Filter Material in Gas Phase Magnesium Purification and Production System Containing It

Abstract

The invention provides the application of elemental silicon filter material in gas-phase magnesium purification. In the gas-phase magnesium purification process, magnesium vapor passes through the elemental silicon filter material. In a certain range of temperature and vacuum degree, elemental silicon will not interact with magnesium vapor on the one hand. The reaction will not form a more stable substance with magnesium in thermodynamics, and will not bring new impurities to the system; on the other hand, the impurities Mn, Al, and Ca in silicon and magnesium vapor have special affinity and can form more Stable solid solution, so as to achieve removal; at the same time, elemental silicon can be used as the nucleation site of certain impurities in magnesium vapor, lowering the nucleation energy barrier, allowing certain impurities to deposit in advance, thereby achieving removal. The invention can effectively remove impurities in the magnesium vapor through the function of the elemental silicon filter material, greatly improve the purity of the magnesium, and the purity of the obtained magnesium is above 99.99%. The production system provided by the invention is suitable for large-scale industrial production, can effectively improve the efficiency of magnesium purification, and reduce the cost of magnesium purification.

Description

technical field [0001] The invention belongs to the technical field of metal magnesium purification, and in particular relates to the application of an elemental silicon filter material in gas-phase magnesium purification and a magnesium purification production system containing the elemental silicon filter material. Background technique [0002] Magnesium alloys are regarded as "21st century green environmental protection engineering structural materials" and important strategic materials because of their high specific strength, high specific stiffness, good electrical and thermal conductivity, excellent damping and shock absorption and electromagnetic shielding performance, and relatively low recycling costs. However, as the foundation of the entire magnesium industry, primary magnesium faces the chronic problems of many types of impurity elements and large fluctuations in content, which often seriously deteriorates the corrosion resistance of magnesium alloys and their pra...

AI Technical Summary

Problems solved by technology

The advantage of the former is that it can realize large-scale purification of raw magnesium, but since the refining agent does not react with impurity elements such as Mn, Al, Fe and Ni in reducing magnesium ingots, it is difficult to produce magnesium with a purity of more than 99.95%; the latter has the advantage It is possible to prepare ultra-high-purity magnesium with a purity of up to 99.9999% (excluding Zn content). The disadvantage is that the preparation efficiency is low and the cost is high, which cannot meet the needs of industrialized large-scale production.

[0004] Chinese patents CN203429230U, CN208562489U, and CN201024206Y mention that "catchers", "interceptors" or "filters" are set at the mouth of the Pidgeon method reduction tank, and some special geometric structures are set at the mouth of the Pidgeon method reduction tank to intercept dust or certain Some pre-condensates, but the overall purification effect is limited, and it is impossible to remove one or several impurities in a targeted manner

[0005] Patent CN206512263U uses graphite to make a filter device, which is placed between the Pidgeon method reduction tank and the condenser, and has a filtering effect on Mn, but high-purity graphite is easy to oxidize and fail at high temperature

Although the patent CN205368470U mentions that there are fillers in the filter, it does not specify the type of material

[0006] Patent JP2018145480A provides an effective high-purity magnesium purification method and purification equipment that discloses the use of SUS fibers and copper fibers as filter materials, but generally stainless steel fibers or stainless steel fibers combined with copper fibers are used as filter materials, and stainless steel is not suitable for magnesium vapor pressure. The working condition of too high is suitable for the working condition of low heating temperature-low temperature sublimation, so the efficiency of magnesium purification is low, and the output of high-purity magnesium is extremely low

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