Separation of Ti(IV) and Fe(III) from Aqueous Sulphate Solution by Cyanex272 [Bis(2,4,4-Trimethylpentyl) Phosphinic Acid] in Kerosene

摘要

Extraction and separation of Ti(IV) and Fe(III) from aqueous sulphate solution by Cyanex 272 [bis(2,4,4-trimethylpentyl) phosphinic acid] in kerosene was investigated. Extraction of Ti(IV) and Fe(III) increased with theincrease of extractant concentration and decreased with the increase of aqueous phase acidity. About 95% Ti(IV) and24% Fe(III) was extracted with 0.20 M Cyanex 272 and 0.25 M H_2SO_4. It was thought that Fe( III) extracted in theorganic phase by the formation of the species FeA_3 or FeA_3(HA)_3and Ti(IV) as TiO_2.A,. Data shows that Cyanex 272can be used as a very effective extractant for Ti( IV) extraction from ilmenite leach solution at high acidity showing largeseparation coefficient for Ti( IV) from [Ti(IV) and Fe(III)] mixture. The maximum separation factor (β=116.50) wasobtained at moderate acidity (0.90 M H_2SO_4) with high extractant (0.20 M Cyanex 272) concentration. The experimen-tal data also suggested that the extraction of Ti(IV)) and Fe(III) by Cyanex 272 did not follow simple extractionmechanism for all the acid ranges. It is likely that solvation mechanism may be operative at high acidity of the aqueousphase.