Abtrennung von Schwermetallen aus natürlichen Wässern an anorganischen Sorbentien (TiO2, ZrO2, Al2O3)

Radioactivity: A Tool to Explore the Past

“…Therefore, sorption of radionuclides on solids has been investigated extensively for materials in the neighbourhood of planned high-active waste repositories [3,184], Sorption of radionuclides on solids may be due to various kinds of interactions [185][186][187]: Fixation by predominantly ionic bonds (ion exchange), by mainly covalent bonds (chemisorption), by weak (van der Waals) bonds (physisorption); sorption on the outer surface of the solids (substantial quantity: outer surface area), sorption on inner surfaces (substantial quantity: inner surface area), sorption by ion exchange at positions within the solids, sorption by precipitation, coprecipitation, or incorporation (one directional processes). In all cases the surface and exchange properties of the solids, in particular the quality of the sorption and exchange sites, are important, as well as the knowledge of the species of the radionuclides in the aqueous system [137,185,[188][189][190][191][192][193][194][195][196][197], in order to understand the migration behaviour of radionuclides.…”

Ion exchange and liquid column chromatography

“…Other exchangers whose special uses are noted are hafnium and thorium phosphates (25,104), cerium(III) oxalate (8), tungsten(VI) oxide and zirconium tungstate (102), zirconium molybdate (165), and copper(II) ferrocyanide (261). Aluminosilicate molecular sieves were used to separate glucose and fructose (531), and hydrous oxides of aluminum, titanium, and zirconium removed traces of heavy-metal ions from water (306).…”