Analysis of a NDSX process for the selective removal of Cd from phosphoric acid

In this work an analysis of the separation process of Cd from phosphoric acid by means of nondispersive solvent extraction technology and by using Aliquat 336 as the selective extractant and water as the backextractant solution is presented. Based on the results of a previous literature report for a different type of extractant, experimental planning, has been carried out to determine the feasibility of cadmium removal in a continuous process that includes a regeneration step of the extractant to its chloride form. A chemical mechanism for the separation process has been proposed. Analysis of the steady-state results of Cd transport from the feed acidic phase to the stripping phase led to evaluation of the membrane mass transport parameter, K-m = 1.76 x 10(-8) m/s.