Refining method of producing high purity metal from crude metal by thermal decomposition of iodide based on the principle of chemical transfer reaction
Based on the principle of chemical transfer reaction, a refining method for preparing high purity metal from crude metal by thermal decomposition of iodide.The overview diagram shows 99.9% pure titanium.
In 1925, A.E. Van Arkel and J.H.de Boer from Germany were first applied to the purification of titanium and zirconium, which is also called Van Arkel method.Some people also call iodine“Catalytic distillation”(catalytic disintegration) method.This method has been successfully applied to the production of small quantities of high-purity metals such as titanium, zirconium, hafnium, vanadium, silicon, chromium, uranium, thorium, etc.
If impure titanium is treated with iodine vapor at 323-523K, volatile iodide will be generated.When the iodide vapor is heated to 1673K through the tungsten wire, the compound will be decomposed, and the pure metal will be deposited on the tungsten wire, and then the iodine obtained from the decomposition will be recycled.
High purity hafnium deposited on tungsten wire
Hafnium crystal with 99.9% purity deposited on tungsten wire
However, the cost of industrial scale production is high.
Bibliography
Announce
edit
W.D.Jamrack,Rare Metals Extraction by ChemicalEngineering Techiques,Pergamon,London,1963.
