The Extraction of Anionic Beryllium Complexes by Tri-iso-octylamine

Abstract

The extraction of beryllium from aqueous solution by long-chain tertiary amines has been observed in the presence of ligands giving rise to anionic complexes. The nature of the oxalate complex extracted by solutions of tri-iso-octylamine in chloroform has been studied in detail and the species formed in the organic phase were shown to have the composition Be(C₂O₄)₂.{NH(i-C₈H₁₅)₃}₂. The complexes formed in aqueous solution between beryllium and several anionic complexing agents have been examined by the method of pH-titration. Conditional stability constants have been obtained for the complexes formed with oxalic, malonic, maleic, succinic, phthalic, and salicylic acids. Differences in their extractabilities can be explained semiquantitatively with the help of the stability constants and the acid association constants of the complexing agents.