- Library Home /
- Search Collections /
- Open Collections /
- Browse Collections /
- UBC Theses and Dissertations /
- Minor element behavior in the INCO CRED process
Open Collections
UBC Theses and Dissertations
UBC Theses and Dissertations
Minor element behavior in the INCO CRED process Qin, Guoming
Abstract
In LNCO's Copper Refinery Electrowinning Department (CRED) the copper sulfide residue containing precious metals (referred as the first stage cake), is subjected to an oxidative pressure leach. The leach - referred as second stage leaching, produces a copper sulfate solution and basic copper sulfate. The basic copper sulfate is releached with spent electrolyte from copper electrowinning containing sulfuric acid to produce impure copper sulfate solution and a precious metals residue. A sample of first stage cake from INCO CRED was shipped to UBC and treated under second stage leaching conditions. The minor element behavior in the process was the objective of the study. The minor elements include cobalt, iron, arsenic, antimony, bismuth, selenium, tellurium and tin. Four important factors that might affect the behavior of minor elements were investigated: Cu/Acid ratio in the feed, Cu/S ratio in the feed, impurity levels in the feed and degree of oxidation. Four series of experiments were performed with filtrate solutions and solid residues analyzed by ICP scan for chemical compositions. Selenium was the minor element of greatest interest due to the difficulty in removing Se from the CRED impure leach solution. Selenium species if present will contaminate copper cathodes and therefore must be removed. The two principal forms of selenium in the CRED streams are believed to be selenite (SeIV) and selenate (SeVI), respectively. INCO CRED had a great concern about selenium speciation in the second stage leaching, which will help to understand the behavior of selenium better and remove it more efficiently. A method for selenium analysis was developed, which was based on Atomic Fluorescence Spectrometry with Hydride Generation (AFS-HG). A pretreatment process was applied to suit the samples in the project and eliminate interferences in Se analysis caused by sulfate and cations. This method was initially applied to samples generated in the UBC lab work. In addition, some samples were taken from INCO CRED plant and analyzed by this method.
Item Metadata
Title |
Minor element behavior in the INCO CRED process
|
Creator | |
Publisher |
University of British Columbia
|
Date Issued |
2005
|
Description |
In LNCO's Copper Refinery Electrowinning Department (CRED) the copper sulfide residue
containing precious metals (referred as the first stage cake), is subjected to an oxidative
pressure leach. The leach - referred as second stage leaching, produces a copper sulfate
solution and basic copper sulfate. The basic copper sulfate is releached with spent electrolyte
from copper electrowinning containing sulfuric acid to produce impure copper sulfate
solution and a precious metals residue.
A sample of first stage cake from INCO CRED was shipped to UBC and treated under
second stage leaching conditions. The minor element behavior in the process was the
objective of the study. The minor elements include cobalt, iron, arsenic, antimony, bismuth,
selenium, tellurium and tin. Four important factors that might affect the behavior of minor
elements were investigated: Cu/Acid ratio in the feed, Cu/S ratio in the feed, impurity levels
in the feed and degree of oxidation. Four series of experiments were performed with filtrate
solutions and solid residues analyzed by ICP scan for chemical compositions.
Selenium was the minor element of greatest interest due to the difficulty in removing Se from
the CRED impure leach solution. Selenium species if present will contaminate copper
cathodes and therefore must be removed. The two principal forms of selenium in the CRED
streams are believed to be selenite (SeIV) and selenate (SeVI), respectively. INCO CRED had
a great concern about selenium speciation in the second stage leaching, which will help to
understand the behavior of selenium better and remove it more efficiently. A method for
selenium analysis was developed, which was based on Atomic Fluorescence Spectrometry
with Hydride Generation (AFS-HG). A pretreatment process was applied to suit the samples
in the project and eliminate interferences in Se analysis caused by sulfate and cations. This
method was initially applied to samples generated in the UBC lab work. In addition, some
samples were taken from INCO CRED plant and analyzed by this method.
|
Extent |
6486148 bytes
|
Genre | |
Type | |
File Format |
application/pdf
|
Language |
eng
|
Date Available |
2009-12-02
|
Provider |
Vancouver : University of British Columbia Library
|
Rights |
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.
|
DOI |
10.14288/1.0078655
|
URI | |
Degree | |
Program | |
Affiliation | |
Degree Grantor |
University of British Columbia
|
Graduation Date |
2005-05
|
Campus | |
Scholarly Level |
Graduate
|
Aggregated Source Repository |
DSpace
|
Item Media
Item Citations and Data
Rights
For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use.