Electronic Thesis and Dissertation Repository


Master of Science




Dr. Brian Hart


Carbonaceous gold ores have the ability to adsorb gold (I) cyanide from leach solutions during processing. This phenomenon, known as preg-robbing, is responsible for poor recoveries as the carbonaceous materials of the ore compete with activated carbon used during the leaching and adsorption phase of processing. Chemical oxidation of carbonaceous materials by different reagents has been utilized to investigate and compare the mechanism of Au (CN)2 adsorption onto carbonaceous materials prior to and following the treatment.

The procedure for characterization of the carbonaceous materials (plain and modified) in the sample combines the use of several analytical techniques and test assays such as Scanning Electron Microscope (SEM), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET), Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS), Raman spectroscopy, Ultraviolet visible (UV-Vis) and Atomic Absorption (AA) in order to provide complete information on all the variables affecting preg-robbing capacity, namely its composition, degree of C disorder, surface area and surface chemistry. This thesis investigated the surface chemistry and surface structure of various carbonaceous materials in the context of factors governing adsorption characteristics towards providing a better estimation of the preg-robbing capacity and strategies for its reduction.