CYANEX 925 As Potential Extractant For the Extraction and Separation of Zirconium (IV) And Niobium (V) From nitric acid Solution

The potential use of CYANEX 925 in kerosene for the extraction and separation of Zirconium (IV) and Niobium (V) from nitric acid solution is explored. The effects of the different parameters affecting the extraction process as extractant, metal, nitric acid and nitrate concentrations as well as temperature were separately investigated. Stripping investigations on the recovery of Zr(IV) and Nb(V) from their loaded organic solutions were also carried out. The obtained results indicate that the extracted metal species are Zr(NO‌3)‌‌4.CYANEX 925 and Nb(OH)2(NO‌3)3.CYANEX 925 for Zr(IV) and Nb(V), respectively. The difference in the extraction and stripping behavior of the investigated metals indicated that a good separation between Zr(IV) and Nb(V) could be obtained when carrying out the extraction from low nitric acid concentration at low temperature or when using 1M sulphuric acid for stripping 99% of Zr(IV) with nearly no stripping of Nb(V) from the loaded organic solution. The obtained results indicate that CYANEX 925 is a promising extractant for high extraction and separation of Zr(IV) and Nb(V) from nitric acid solution compared with other organophosphorus extractants.