Extraction of zinc(II) in hollow fiber modules

The recovery of zinc(II) from model hydrochloric acid solutions with tributyl phosphate in hollow fiber modules was studied. The experimental results suggested that zinc(II) can be effectively removed from investigated solutions. A mass transfer model of the process was formulated and verified. The model satisfactorily reflected the experimental profiles of zinc concentration. Recovery of zinc(II) was different depending on TBP concentrations. In case of low TBP concentration (40%) the kinetics of the process was limited by the diffusion of species within the membrane pores. Maximum achievable flux was obtained. Thus, the flowrates did not influence the mass transfer coefficient. The increasing of both feed and organic phase flowrates improved the mass transfer when 80% TBP was used. The flux of zinc(II) could be still increased within the flowrates' region covered in the work.