Sludges formed by lime treatment of acidic mine effluents are a widespread environmental hazard. One treatment option is to recover the toxic and potentially valuable contained metals. A method has been reported to selectively recover the metals by leaching with a complexing agent, diethylenetriamine (DETA). In this thesis a novel method has been developed to recover metals from the metal---DETA complexes by direct electrowinning. Copper was studied initially as a test system due to the relative ease with which it is recovered in conventional sulphate electrowinning. The main industrial interest, and hence the main focus of the work, is in the nickel---DETA system. For both metals, initially batch tests were run to determine acceptable electrowinning conditions. These were followed by recycle tests to simulate a potential process flowsheet. In the nickel-DETA system the effects of pH, nickel concentration, temperature, and DETA to nickel ratio on current efficiency were determined. / Recycle tests for copper showed that a steady DETA concentration was achieved after ca. six hours. In the case of nickel, the system seemed to continually deteriorate. A pH range of 4.6 to 4.8 maximized the current efficiency, due to a competition between hydrogen formation at low pH and increased complex stability at high pH. Both increasing Ni concentration and temperature increased the current efficiency, while increasing the DETA to nickel ratio lowered it.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:QMM.33329 |
| Date | January 2000 |
| Creators | Felsher, Dave. |
| Contributors | Finch, J. A. (advisor) |
| Publisher | McGill University |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Format | application/pdf |
| Coverage | Master of Engineering (Department of Mining and Metallurgical Engineering.) |
| Rights | All items in eScholarship@McGill are protected by copyright with all rights reserved unless otherwise indicated. |
| Relation | alephsysno: 001780272, proquestno: MQ70638, Theses scanned by UMI/ProQuest. |
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