Solvent Extraction and Stripping of Tetravalent Titanium from Acidic Chloride Solutions by Trioctylphosphine Oxide

The solvent extraction and stripping of titanium(Ⅳ) from acidic chloride solutions by trioctylphosphine oxide（TOPO） in kerosene has been investigated. The solvent extraction results demonstrate that the extracted titanium is present as TiCl 4 .2TOPO. The kinetics of the extraction process is very fast, since the equilibrium is reached in 5 min. In addition, the extraction of titanium (Ⅳ) increases with the total chloride concentration in the aqueous phase, as well as with the extractant concentration in the organic phase. The loading capacity of TOPO for titanium (Ⅳ) is 4.60g/100g TOPO. The stripping results show that when the O/A phase radio changing from 1 to 10, titanium (Ⅳ) is completely stripped from the mental loaded organic phase of TOPO with 1 mol dm-3 hydrochloric acid. Thus titanium (Ⅳ) can be enriched to tenfold concentration by the stripping.