Utilization of iodide as a perchlorate-laden resin regenerating solution and isolation of perchlorate from simulated ground water samples

The selective ion exchange of perchlorate from simulated groundwater samples using the bifunctional Purolite A-530E resin was performed. Regeneration of the resin is difficult due to the relatively hydrophobic nature and high selectivity of perchlorate over the most common ions. Use of the tetrachloroiron(III) complex in 2 M or higher hydrochloric acid solutions as a regenerant and displacer of perchlorate can be problematic if one wishes to recover the perchlorate and/or use stainless steel columns, fittings, and HPLC-type pumps. 0.1 M sodium iodide was investigated as an alternative to FeCl4− to circumvent these problems. Regeneration efficiencies in between those of FeCl4− and Cl− were observed. During elution a peak fraction of 0.068 M NaClO4 in 0.1 M NaI was obtained. Pure KClO4 was then precipitated by addition of KCl and methanol to this fraction.