Electrochemistry and separation of transition metals with biodegradable ligands

[摘要] ENGLISH ABSTRACT:The electrochemical analysis of selected metal ions with the newly biodegradablechelating agents, lminodisuccinic acid (IDS) and Polyaspartic acid (PASP) wasperformed by cyclic voltammetry using a thin mercury film glassy carbonmicroelectrode. IDS and PASP are of interest from an environmental perspective. Theywere introduced as alternatives to chelants and dispersants.The thermodynamic stability constants of these selected metal complexes weredetermined by cyclic voltammetry (CV). A comparison with similar data obtained usingpotentiometric methods shows a good correlation between the two methods. Thisreaffirms that CV is a useful and facile means for evaluating metal-ligand complexthermodynamic data. Furthermore, our results were used to validate the predicted modelsobtained using an Equilibrium Speciation model JESS program.Capillary Electrophoresis (CE) was used to separate metal-IDS and metal-PASPcomplexes at different pH's. The separation of these chelates was achieved within 7minutes. The obtained results were compared with speciation and a reasonable agreementwas observed, although the separation ofmetal-PASP showed poor broad peaks.

[发布机构] Stellenbosch University