The proposed technology involves a pretreatment process to remove unwanted elements in commercial powders. The process involves treating powders in ultra-high vacuum with or without concurrent heating for extended period of time. In this process the impurities (predominantly the anionic species) are removed from the powders without any changes in the physical characteristics (such as particle size and particle size distribution, surface area, volume etc).
Issued Patent - #8,440,584
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