Selective Sorption of Cerium Ions from Uranium-Containing Solutions by Remotely Activated Ion Exchangers

This study investigated the effect of the remote activation of the ion exchangers Amberlite IR120 (H⁺ form) and AV-17-8 (OH^- form) in aqueous media to increase the sorption activity of the interpolymer system "Amberlite IR120H:AV-17-8" (X:Y, molar ratio of ionic groups) towards cerium ions from uranium-containing solutions. The sorption properties of the above-mentioned interpolymer system with molar ratios X:Y of 6:0, 5:1, 4:2, 3:3, 2:4, 1:5, and 0:6 were studied using the methods of conductometry, gravimetry, and inductively coupled plasma-optical emission spectrometry. The presented research revealed the dependence of the sorption activity of the interpolymer system "Amberlite IR120H:AV-17-8" (X:Y) on the acidity of the solution. At pH 2.0, the highest cerium ion sorption degree from the model solution (containing both cerium and uranium ions) by the interpolymer system "Amberlite IR120H:AV-17-8" (4:2) was 56% after 48 h of interaction, whereas the cerium ion sorption degrees by raw Amberlite IR120H (6:0) and raw AV-17-8 (0:6) were 30% and 0%, respectively. The increased sorption ability of the interpolymer system "Amberlite IR120H:AV-17-8" (4:2) might be associated with the achievement of the highest ionization degree by this system remotely activated in an aqueous medium. Moreover, the cerium ion desorption study demonstrated a 60% degree of desorption using 2M nitric acid as a desorbing agent (eluent). The obtained results demonstrate the potential of using the remote interaction effect for the activation of the ion exchangers in aqueous media as an interpolymer system for increased cerium ion sorption from uranium-containing solutions.