| 摘要 |
Presented herein is a ligand-assisted elution chromatography process for the separation of metal ions using a sorbent. An inorganic sorbent, titania, for example, has three types of adsorption sites: Bronsted acid (BA), Bronsted base (BB), and Lewis acid (LA). At a high pH, the BA sites can interact with the metal ions as a cation exchanger. If a ligand with COOgroups is preloaded onto the sorbent, the COO- groups of the ligand can adsorb onto the LA sites. The adsorbed. ligands become strong adsorption sites for the metal ions. If the Langmuir a value for metal ion adsorption is similar to that of metal ion complexation with the ligand in the mobile phase, the different metal ions can be eluted separately with an overall selectivity which is equal to the ratio of the ligand selectivity to the sorbent selectivity. |
