Cyanides mineral processing

J. L. Huiatt and co-workers, eds.. Proceedings of a Workshop—Cyanide Erom Mineral Processing, University of Utah, Salt Lake City, 1982. 

G. J. Sparrow and J. T. Woodcock, Cyanide and Other Lbdviant Leaching Systems for Gold with Some Practical Applications, Mineral Processing and Extractive Metallurgy Review, Nos. 3 4, Vol. 14, p. 193, 1995. 

Huiatt JL. 1985. Cyanide from mineral processing Problems and research needs. Conf. Cyanide and Environment, Tuscon, AZ, December 1984. Published by Geotechnical Engineering Program, Colorado State University, Fort Collins, CO 65-81. 

Extractive industries include mining of mineral deposits (principally metal-bearing ores and coal deposits), oil and natural gas production, and quarrying for building and roadmaking materials. Poorly operated or abandoned mine sites are often significant sources of water contamination contaminants of particular health concern from these sources include heavy metals, and mineral-processing chemicals, such as cyanide. 

Arslan, R, Ozdamar, D.Y, and Muduroglu, M. 2003. Cyanidation of Turkish gold-silver ore and the use of hydrogen peroxide. European Journal of Mineral Processing and Environmental Protection, 3 309-15. 

The CE for the cyanide destruction process is obviously determined by the extent of the parallel reaction (7), a factor which becomes much more important as the cyanide levels drops to below 100 ppm [88]. Complete mineralization of the CN-by reaction (8) removes all traces of the offending species, but at the expense of considerably more charge consumption. It may be reasonable to stop the reaction at the CNO- stage, something which is quite feasible since reaction (8) occurs with more difficulty than (6) [89] at a potential of almost 0.5 V more anodic [87]. At a PH < 10, the cyanate ion hydrolyzes on its own according to the following reaction ... 

Mudder, T. I., Botz, M. M. (2004). Cyanide and society A critical review. European Journal of Mineral Processing Environmental Protection, 4(1), 62-74. 

Muir, D. M., Aylmore, M. G. (2004).Thiosulphate as an alternative to cyanide for gold processing -issues and impediments. Mineral Processing and Extractive Metallurgy, 113(1), 2-12. 

R. Y. Wan, and J. D. Miller, Research and Development Activities for the Recovery of Gold from Alkaline Cyanide Solutions, Mineral Processing and Extractive Metallurgy Review, 6, 143-190 (1989). 

L. C. Thompson and R. L. Gerteis, New Technologies for Mining Waste Management—Biotreatment Processes for Cyanide, Nitrates and Heavy Metals, in Mining and Mineral Processing Wastes, F. M. Doyle (ed.), SME, Littleton, CO, 271-278 (1990). 

K. P. Galvin, M. D. Engel, and S. K. Nicol, "The Selective Ion Flotation of Gold Cyanide from a Heap Leach Mine Feed Liquor, Proceedings XVlll International Mineral Processing Congress, Sydney, Australia, Austr. IMM. 

Spraying large piles of gold ore with a toxic cyanide solution in the open is a somewhat dicey operation, despite which very few workers have died from accidental cyanide exposure in the process. Some significant fish kills have resulted from discharge of cyanide from mineral processing operations into waterways. 

Hydrogen Cyanide Process. This process, one of two used for the industrial production of malonates, is based on hydrogen cyanide [74-90-8] and chloroacetic acid [79-11-8]. The intermediate cyanoacetic acid [372-09-8] is esterified in the presence of a large excess of mineral acid and alcohol. 

The pH of the pulp to the flotation cells is carefliUy controlled by the addition of lime, which optimizes the action of all reagents and is used to depress pyrite. A frother, such as pine oil or a long-chain alcohol, is added to produce the froth, an important part of the flotation process. The ore minerals, coated with an oily collected layer, are hydrophobic and collect on the air bubbles the desired minerals float while the gangue sinks. Typical collectors are xanthates, dithiophosphates, or xanthate derivatives, whereas typical depressants are calcium or sodium cyanide [143-33-9] NaCN, andlime. 

The CSIRO Division of Mineral Products, Port Melbourne, Victoria, Australia, is conducting research to develop a process to recover fluoride and aluminum from spent pot lining ash with concurrent production of an environmentally safe residue that is suitable for disposal. The proposed method involves initial calcination which thermally decomposes the cyanide in the spent pot lining. Successful completion of this research would reduce the amount of hazardous wastes that contain potentially harmful leachable cyanides that can enter the groundwater during open air storage. 

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