High purity metal purification
Time：2021-11-10 Author：Changsha Xinkang scientific research material service platform
High-purity metal is a metal with high purity, and the impurities are often calculated in parts per million. Special uses are obtained because their properties are significantly different from general industrial pure metals. For example, metals such as germanium, indium, and gallium used in the preparation of semiconductor materials require a purity of more than 99.999%. High-purity metals are also heavily used in research, development, and production of advanced technologies that require the properties, properties, and quality of high-purity metals, as well as high-quality magnetic, thermoelectric, and phosphors. These high-purity metals are used to make fluorescent lamps, plasma screens, LEDs, high-precision lenses and optics, electronic sensors, advanced ceramics, thermal barrier coatings, lasers, and more.
High-purity metal refining
High-purity metal refining is usually carried out in two steps, namely purification (preliminary purification) and ultra-purification (final purification). The production methods are roughly divided into chemical purification methods and physical purification methods.
chemical purification method
The process of separating impurities by means of chemical reactions such as oxidation, reduction, and complexation can be divided into two types: wet method and fire method. The effective means of wet purification are ion exchange (including ion exchange resin, ion exchange fiber, ion exchange membrane, etc.), extraction (organic solvent extraction, extractive distillation, etc.), displacement precipitation (replacement in the order of metal activity), electrochemical method. (aqueous solution electrolysis, controlled potential electrolysis, electrodialysis, electrophoresis, etc.); fire purification mainly includes chloride rectification, iodide thermal decomposition, disproportionation decomposition, melting refining, molten salt electrolysis, electron beam melting, etc.
Physical purification method
A method of removing impurities by physical processes such as evaporation, solidification, crystallization, diffusion, and electromigration. The physical method mostly uses vacuum technology. Some rare metals have strong inhalation properties, and they need to be purified in high vacuum and ultra-high vacuum (above 10-8~10-10 Torr). The purification methods mainly include regional smelting method, single crystal method, vacuum distillation, electrolysis. Migration method and electromagnetic field purification.
Due to the complicated equipment and knowledge involved in high-purity metal extraction, we can only purify a few metal materials at present. 3N5 high-purity vanadium, etc. If you have material requirements in this regard, you can contact us.