Solvent Impregnated Resins Containing Cyanex 272. Preparation and Application to the Extraction and Separation of Divalent Metals.

Impregnatedresinscontaining di-(2,2,4-trimethylpentyl)phosphinic acid (Cyanex272) were prepared by adsorption of the extractant into Amberlite XAD-2 polymeric adsorbant. The distribution of Cyanex272 between the aqueous and resin phase was studied as a function of pH and loading of the organophosphorous extractant on the resin. The concentration of organophosphorous compound was determined by ICP. XAD-2-Cyanex272impregnatedresins were tested for the recovery and separation of Zn(II), Cd(II) and Cu(II) from aqueous solutions. The distribution coefficient of Zn(II), Cd(II) and Cu(II) between the aqueous phase and the resin phase were determined under different conditions. The separation factors between the three metal ions are sufficiently large to allow effective separation of Zn from Cd (100%) and Cu (90%). The selective recovery of Zn(II) from aqueous solutions has been carried out by using SIR as the column stationary phase. The retained metal ions were released from the resin quantitatively by elution with hydrochloric acid solutions at the correct concentration for each metal ion.