Full Text Available
Note: Clicking the button above will open the full text document at the original institutional repository in a new window.
Fundamentals of the flotation behaviour of palladium bismuth tellurides
Thesis (PhD (Metallurgical Engineering))--University of Pretoria, 2006.
Saved in:
| Other Authors: | |
|---|---|
| Format: | Thesis |
| Published: |
University of Pretoria
2013
|
| Subjects: | |
| Tags: |
No Tags, Be the first to tag this record!
|
| _version_ | 1867613453195149312 |
|---|---|
| access_status_str | Open Access |
| author2 | Pistorius, Petrus Christiaan |
| author_browse | Pistorius, Petrus Christiaan |
| author_facet | Pistorius, Petrus Christiaan |
| collection | Thesis |
| dc_rights_str_mv | © 2005, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. |
| description | Thesis (PhD (Metallurgical Engineering))--University of Pretoria, 2006. |
| format | Thesis |
| id | oai:repository.up.ac.za:2263/28676 |
| institution | University of Pretoria (South Africa) |
| last_indexed | 2026-06-10T12:36:23.211Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository |
| publishDate | 2013 |
| publishDateRange | 2013 |
| publishDateSort | 2013 |
| publisher | University of Pretoria |
| publisherStr | University of Pretoria |
| record_format | dspace |
| source_str | UPSpace — University of Pretoria Institutional Repository |
| spelling | oai:repository.up.ac.za:2263/28676 Fundamentals of the flotation behaviour of palladium bismuth tellurides Pistorius, Petrus Christiaan thys.vermaak@postino.up.ac.za Vermaak, M.K.G. (Matthys Karel Gerhardus) Great dyke and pd-bearing bismutho-tellurides Precious metal ores Pgm Platinum flotation Flotation kinetics Microflotation Particle size Ore mineralogy Froth flotation UCTD Thesis (PhD (Metallurgical Engineering))--University of Pretoria, 2006. Previous mineralogical investigations (QemSCAN) performed on all effluent flotation streams of Mimosa mine (Zimbabwe) indicated the presence of appreciable amounts of platinum group minerals (PGMs), which are not recovered. Most, generally in excess of 70%, of the liberated PGMs in these streams belonged to the Pt-Pd-Bi-Te class in all the samples investigated. In the first part of this work, electrochemical investigations, electrochemically-controlled contact angle measurements and Raman spectroscopy have been employed to investigate the interaction of ethyl xanthate with Pd-Bi-Te and PtAs2. Impedance measurements showed lower capacitance values in solutions containing KEX indicating the formation of a continuous surface layer. Anodic and cathodic polarization diagrams show the mixed potential to be higher than the reversible potential of the xanthate-dixanthogen equilibrium reaction, hence the formation of dixanthogen on the surface is possible. Electrochemically controlled in situ Raman spectroscopy has confirmed the co-presence of xanthate with dixanthogen indicating that xanthate retains its molecular integrity when it adsorbs on the surface of the Pd-Bi-Te. The result of this investigation has shown dixanthogen to be present on both the minerals (PtAs2 and Pd-Bi-Te) when the surfaces are anodically polarized. Chemisorbed xanthate could be identified within 120 seconds yielding a hydrophobic surface as indicated by electrochemically-controlled contact angle measurements. Maximum contact angles of 63o were measured in the case Pd-Bi-Te. As a result the mineral surface is expected to be hydrophobic and a lack of collector interaction with the mineral is not the reason for low PGM recoveries experienced. Secondly, the flotation recovery of synthetically prepared Pd-Bi-Te was compared with that of chalcopyrite (a typical fast-floating mineral) and pyrrhotite (a typical slow-floating mineral), with microflotation tests. These indicated Pd-Bi-Te to be a fast-floater with flotation rates exceeding that of chalcopyrite. Predicted flotation rate constants (from the Ralston model) were significantly lower for small particles (with diameters similar to those lost to the effluent streams) compared with those of particle with intermediate sizes. This supports the suggestion that losses to effluent streams are caused by particle size effects. Materials Science and Metallurgical Engineering unrestricted 2013-09-07T14:04:00Z 2005-10-13 2013-09-07T14:04:00Z 2005-05-08 2006-10-13 2005-10-13 Thesis Vermaak, M 2005, Fundamentals of the flotation behaviour of palladium bismuth tellurides, PhD thesis, University of Pretoria, Pretoria, viewed yymmdd < http://hdl.handle.net/2263/28676 > http://hdl.handle.net/2263/28676 http://upetd.up.ac.za/thesis/available/etd-10132005-105623/ © 2005, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf application/pdf application/pdf application/pdf application/pdf application/pdf application/pdf application/pdf application/pdf application/pdf application/pdf University of Pretoria |
| spellingShingle | Great dyke and pd-bearing bismutho-tellurides Precious metal ores Pgm Platinum flotation Flotation kinetics Microflotation Particle size Ore mineralogy Froth flotation UCTD Fundamentals of the flotation behaviour of palladium bismuth tellurides |
| title | Fundamentals of the flotation behaviour of palladium bismuth tellurides |
| title_full | Fundamentals of the flotation behaviour of palladium bismuth tellurides |
| title_fullStr | Fundamentals of the flotation behaviour of palladium bismuth tellurides |
| title_full_unstemmed | Fundamentals of the flotation behaviour of palladium bismuth tellurides |
| title_short | Fundamentals of the flotation behaviour of palladium bismuth tellurides |
| title_sort | fundamentals of the flotation behaviour of palladium bismuth tellurides |
| topic | Great dyke and pd-bearing bismutho-tellurides Precious metal ores Pgm Platinum flotation Flotation kinetics Microflotation Particle size Ore mineralogy Froth flotation UCTD |
| url | http://hdl.handle.net/2263/28676 http://upetd.up.ac.za/thesis/available/etd-10132005-105623/ |