Characterization of Goldstrike ore carbonaceous material
Tóm tắt
Carbonaceous materials (CM) from ores of varying preg-robbing activity from Barrick Goldstrike Mines Inc. (BGMI), Nevada, were characterized in terms of their functional group contents, hydrocarbon contents, elemental compositions and humic acid contents. Fourier transform infrared (FT-IR) analyses did not show the presence of hydrocarbons orcarboxylic, phenolic or suljhydrol functionalities. The FT-IR bands present included C=C stretching in aromatic rings and C-O-C stretching, indicating the presence of oxygen as ether linkages or thiocarbonyl functionality in the carbon matrix. Calculated atomic oxygen to carbon (O/C) ratios did not reveal a trend between the maturity of the CM and the preg-robbing behavior, possibly due to the low resolution inherent in electron microprobe analyses. However, the atomic O/C ratios agree with other chemical analyses, indicating that the organic carbon is very mature, similar to or higher than anthracite grade coal. Gas chromatography-mass spectrometry and nuclear magnetic resonance analyses corroborated the relatively featureless character of the carbon, indicating that the carbon structure is virtually completely aromatic (graphitic).
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