Thesis (MScEng) -- Stellenbosch University , 2001. / ENGLISH ABSTRACT: The electrochemical analysis of selected metal ions with the newly biodegradable
chelating agents, lminodisuccinic acid (IDS) and Polyaspartic acid (PASP) was
performed by cyclic voltammetry using a thin mercury film glassy carbon
microelectrode. IDS and PASP are of interest from an environmental perspective. They
were introduced as alternatives to chelants and dispersants.
The thermodynamic stability constants of these selected metal complexes were
determined by cyclic voltammetry (CV). A comparison with similar data obtained using
potentiometric methods shows a good correlation between the two methods. This
reaffirms that CV is a useful and facile means for evaluating metal-ligand complex
thermodynamic data. Furthermore, our results were used to validate the predicted models
obtained using an Equilibrium Speciation model JESS program.
Capillary Electrophoresis (CE) was used to separate metal-IDS and metal-PASP
complexes at different pH's. The separation of these chelates was achieved within 7
minutes. The obtained results were compared with speciation and a reasonable agreement
was observed, although the separation ofmetal-PASP showed poor broad peaks. / AFRIKAANSE OPSOMMING: Die elektrochemiese analise van geselekteerde metaal-ione met nuwe biodegredeerbare
chelate, Iminodisuksien suur (IDS) en Polyaspartiese suur was gedoen met sikliese
voltametrie deur gebruik te maak van 'n dun laag kwik glasagtige koolstof
mikroelektrode. Vanaf'n omgewingsstandpunt is IDS en PASP van belang. Hulle was
voorgestel as alternatiewe vir chelate en verspreidingsagente.
Die termodinamies stabiliteits konstantes van hierdie uitgesoekte metal komplekse was
bepaal deur middel van sikliese voltametrie (CV). 'n Vergelyking met soortgelyke data,
wat met potensiometriese metodes bepaal was, dui 'n goeie korrelasie aan tussen die twee
metodes bepaal was. Dit bevestig die feit dat CV 'n bruikbare en maklike manier is om
metal ligand komplekse se termodiniese data te evalueer. Die resultate was ook gebruik
om die voorspelde model, wat verkry was deur gebruik te maak van "Equilibrium
Speciation model JESS program, te bevestig.
Kapillere elektroforese (CE) was gebruik om metal-IDS en metal-PASP komplekse by
verskillende pH's te skei. Die skeiding van hierdie chelate was binne sewe minute verkry.
Hierdie resultate was vergelyk met die spesiasie data en 'n aanvaarbare ooreenstemming
was waargeneem, alhoewel die skeiding van die Metaal-PASP swak pieke toon.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/52257 |
| Date | 12 1900 |
| Creators | Katata, L. M. |
| Contributors | Crouch, A. M., Stellenbosch University. Faculty of Science. Dept. of Chemistry and Polymer Science. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | English |
| Type | Thesis |
| Format | 145 p. : ill. |
| Rights | Stellenbosch University |
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