SOLVENT-EXTRACTION OF TITANIUM(IV) WITH 2-ETHYL HEXYL PHOSPHONIC ACIDMONO 2-ETHYL HEXYL ESTER (HEHEHP)

Liquid-liquid extraction of titanium(IV) from sulfuric acid solution u sing 2-ethyl hexyl phosphonic acid mono 2-ethyl hexyl ester (PC-88A) i n toluene has been studied. The extraction of titanium(IV) was found t o he quantitative with 0.03 M PC-88A in toluene in the acidic range of 0.01-0.3 M and 12.0-14.0 M H2SO4. Titanium(IV) extracted in the organ ic phase was stripped with the mixture of 2.0-3.5 M H2SO4 and 3% H2O2. Effect of reagent concentration on the extraction of titanium(IV) was studied. The stoichiometry of the extracted species of titanium(IV) w as determined on the basis of slope analysis method. The extraction re action proceeds with cation exchange mechanism in the range of 0.01 M- 0.3 M H2SO4 and the extracted species is in the TiOR2. 2HR form and at higher acidty (12.0 M-14.0 M H2SO4) it proceeds by solvation, the ext racted species is Ti(OH)(3)HSO4. 4HR. Temperature dependence of the ex traction equilibrium constants was examined to estimate the apparent t hermodynamic functions (Delta H, Delta S and Delta G) for extraction r eaction.