Thorium pertraction through hollow fiber renewal liquid membrane (HFRLM) using Cyanex 272 as carrier

In this study, continuous extraction and back extraction of Th(IV) is carried out in the hollow fiber renewal liquid membrane (HFRLM) process. The organic solution of bis(2,4,4-trimethylpentyl) phosphininc acid (Cyanex 272) diluted in kerosene is used as a liquid membrane phase which could transport thorium ions from the aqueous nitrate solution of donor phase to the acceptor phase containing H2SO4. The experiments are performed in the fashion that a mixture of aqueous and organic phase in the volume ratio of (A/O) 20 flows through the lumen side while the aqueous acceptor phase is pumped through the shell side. Results indicate the satisfactory stability of HFRLM process during 10 h of continuous operation. In addition, results show that the increase in the velocity of fluid in the lumen side, concentration of cyanex 272 in the liquid membrane phase, and pH of the feed leads to increase the mass transfer flux. However, increase in the H2SO4 concentration of acceptor phase from 0.2 to 1 mol.L−1 and initial concentration of thorium (IV) has no significant effect. In addition the overall mass transfer coefficient are calculated in the range of 5.7×10−8 to 2.41×10−7m/s.