Thesis (MSc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The determination of the concentrations of the transition metals Mn2
+, Cu2
+ and Fe3
+
in various types of pulps was carried out using a combination of chelation with
Ethylenediaminetetraacetic acid (EDTA) and ethylenediaminedisuccinic acid (S,SEDDS)
and capillary zone electrophoresis (CZE) coupled with diode array uvdetection.
The metals were found to be inhomogeneously distributed in the pulps, and
therefore a relatively large (20 gms) pulp samples were taken for analysis. Heating the
pulp samples at 45°C with stirring for three hours was used to leach the metals into
an aqueous phase for complexation with the ligands. Leaching with EDTA enabled
the quantitative determination of 0.0091,0.0048 and 0.0014 mM Cu2
+ and 0.0088,
0.0012 and 0.0016 mM Mn2
+ in the three types of pulps analyzed respectively while
detection of Fe3
+ was not possible using EDTA. The use of [S,S-EDDS] as the
leaching agent on the other hand enabled the quantitative determination of 0.0041,
0.0036 and 0.0031 mM Cu2+ and 0.0024, 0.0018 and 0.0047 mM Fe3+ in the three
types of pulps analyzed respectively while determination of Mn2
+ was not possible
using [S,S-EDDS] as the leaching agent. [S,S-EDDS] was generally better in
complexing iron and copper than EDTA. The leaching procedure employed and the
detectors response to specific analytes formed were found to be the most important
factors in the analysis of the metals in pulp. / AFRIKAANSE OPSOMMING: Die konsentrasies van die oorgangsmetale Mn2
+, Cu2
+ and Fe3
+ in verskeie tipes pulp
is bepaal met behulp van 'n kombinasie van kelasie met etileendiamientetra-asynsuur
(EDTA) en etileendiamiendisuksiensuur (S,S-EDDS) en kapillêre elektroforese (CE)
gekoppel met UV-deteksie. Daar is bevind dat die metale oneweredig versprei is in
die pulp monsters, en gevolglik is relatiewe groot (20 g) monsters gebruik vir die
analiese. Die metale is ge-ekstraeer deur kompleksasie met die kelasie-agente in die
water-fase, deur die pulp monsters vir drie uur te roer by 45°C. Ekstraksie met EDT A
is gebruik om 0.0091,0.0048 en 0.0014 mM Cu2
+ en 0.0088,0.0012 and 0.0016 mM
Mn2
+ in drie tipes pulp te bepaal, terwyl Fe3
+ nie waargeneem is met behulp van
EDTA nie. Deur [S,S-EDDS] te gebruik as ekstraksie-agent, is 0.0041, 0.0036 en
0.0031 mM Cu2+ en 0.0024, 0.0018 en 0.0047 mM Fe3+ in die drie tipes pulp
waargeneem. Die analise van Mn2
+ was nie moontlik met die metode nie. Daar is
gevind dat die keuse van ekstraksie metode en die detektor-sensitiwiteit vir spesifieke
metale die mees bepalende faktore in die analise van metale in pulp monsters is.
EDDS was 'n beter keiaat vir Fe3
+ en Cu2
+ as EDTA.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:sun/oai:scholar.sun.ac.za:10019.1/49906 |
| Date | 12 1900 |
| Creators | Goje Tesfai, Tedros |
| Contributors | Crouch, A. M., Stellenbosch University. Faculty of Science. Dept. of Chemistry & Polymer Science. |
| Publisher | Stellenbosch : Stellenbosch University |
| Source Sets | South African National ETD Portal |
| Language | en_ZA |
| Detected Language | English |
| Type | Thesis |
| Format | 76 p. : ill. (some col.) |
| Rights | Stellenbosch University |
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