NSERC I2I phase I application - a new process for selective extraction of gold from gold ore: an alternative to the cyanide process applicable to the gold mining industry

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We are developing the best technology for selective extraction of gold from gold ore to completely replace the cyanidation process applicable to the gold mining industry. Overall advantages of our technology include increased simplicity, lower costs, considerably shorter extraction times (at room temperature) while providing a clean, safe and environmentally friendly alternative to the existing cyanidation process. The cyanidation process is the dominant technique for extraction and recovery of gold from ore due to the high leaching efficiency and mature technology of the operation. The process involves dissolution of gold from ore in a sodium cyanide solution, following which the resulting gold cyanide complex is extracted from the solution by activated carbon adsorption. The gold complex is then removed from the activated carbon by further addition of a basic sodium cyanide solution and then reduced to elemental gold. The use of large amounts of sodium cyanide remains extremely controversial and is of great environmental concern. Research efforts have been made to find other appropriate alternative methods. Solvent extraction techniques, which have been widely used in the recovery of various metals in hydrometallurgical processes, is a promising technique to overcome these problems because it has a number of advantages including simple technology, high production capacity, fast extraction kinetics, high selectivity and high product purity. As a result, studies on the direct solvent extraction of gold from cyanide solution have received considerable attention. However, no solvent extraction system has ever been successfully implemented in the industrialization of gold production. Canada is the seventh largest gold producer in the world producing about 100 tonnes of gold per year, however Canada remains a major player in the world gold market with 75% of the world's mining companies being headquartered in Canada. With funding from the NSERC I2I program, we will move this technology into the hands of Canadian mining companies to be licensed and implemented in gold mining operations around the world.