Statistical Experimental Design for the Extraction of Ti(IV) in the Ti(IV)-SO₄^2- (H⁺, Na⁺) – Cyanex 301 – Kerosene – 5% (v/v) Heptane-1-ol System

Abstract

The titled system has been investigated from the modelling point of view. The equilibration time for the system is 45 min, and 5% (v/v) heptane-1-ol in the organic phase is used as a  de-emulsifier. The factors affecting the extent of extractions are [Ti(IV)], pH_(eq), [Cyanex 301], [SO₄^2-] and temperature (T). The selected levels are high (+) and low (-) for these factors in the present investigation. Model equation for the extraction of Ti(IV) by Cyanex 301 is determined from 2⁵ full factorial design. However, the success of the factorial design depends on the linear relationship between yield and factor. Plots of log ^CD vs log [Ti(IV)], pH_(eq), log [Cyanex 301] and log [SO₄^2-] are curves. Logistic functions involving these factors are considered in designing. While [Ti(IV)] < 1.00 g/L and [HA]_(o) > 0.10 mol/L, considered logistic functions viz. -log(1+316.2 ([Ti(IV)], mol/L)), -log (10^-pH + 229 ´10^-2pH), log ([HA]_(o), mol/L), -log (1+0.79 ([SO₄^2-], mol/L)) and absolute temperature are abbreviated as M, P, E, S and T, respectively. Model is log ^CD = 5.847 + 0.964 M + 0.909 P + 2 E + 0.995 S – (1437.5/T). The experimental model illustrates that there is no interaction effect between the factors under investigation.