Studies on inorganic ion exchangers. Part 1. Preparation, properties and application of cerium(IV) arsenite

Abstract

Studies on the synthesis, composition and ion-exchange properties of cerium(IV) arsenite have been carried out. This exchanger is stable in water, ethanol, acetic acid, H₂SO₄(2 M), HNO₃(1 M) and in solutions of LiCl, MgCl₂, CaCl₂ and BaCl₂. It retains about 50% of its exchange value after drying at 100 °C. It can be regenerated twice without any appreciable decrease in exchange capacity. The empirical formula proposed is CeO₂.As₂O₃.5H₂O; the cerium to arsenite ratio was calculated from titrimetric and gravimetric analyses. Cerium(IV) arsenite shows a high affinity for Pb^II, Hg^II, Sn^II, Bi^III, Ca^II and Th^IV. Six binary separations ranging from 98 to 100% have been achieved on cerium(IV) arsenite columns.