M.Sc. / The metallurgical industrial losses of base metals with waste solutions are an environmental threat to water sources, hence these metal ions must be removed prior to discharge into receiving bodies. In this study, Southern African clinoptilolite’s capability as an ion-exchanger with respect to Cu2+ and Co2+ was investigated in order to consider its application in metal cation removal from aqueous solutions. The clinoptilolite was characterised with X-ray powder diffraction (XRD), X-ray fluorescence (XRF), FTIR, thermogravimetric analyser (TGA) and SEM-EDS. The clinoptilolite was found to be a thermally stable alumino-silicate with calcite, dolomite and quartz as the main minerals. Investigations of Co2+ and Cu2+ uptake were first performed on non-mixed solutions of these cations. It was found that Cu2+ was removed faster than Co2+ with removal efficiencies of 79% and 63% respectively. The column method was used in the cation-exchange processes with synthetic solutions of 0.0020 M, 0.0698 M and 0.2000 M of Co2+ and Cu2+ concentrations which were measured using atomic absorption spectroscopy (AAS). The effects of Co2+ and Cu2+ ions on one another’s removal efficiency were investigated on Co/Cu mixed synthetic solutions by varying their concentration ratios in solution. The Cu2+ was generally found to be removed at lower rates than the Co2+. Investigations on added impurities in the form of Si4+ and Fe2+ in the mixed Co/Cu synthetic solutions were carried out to determine their effect on the removal efficiencies of the targeted metals. It was found that both Si4+ and Fe2+ greatly reduced the removal efficiency of Cu2+, especially with increased amounts of Si4+ in the Co/Cu solution.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:uj/uj:7054 |
| Date | 02 March 2011 |
| Creators | Nyembe, Dumsile W. |
| Source Sets | South African National ETD Portal |
| Detected Language | English |
| Type | Thesis |
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