Depressants mineral processing

Hu Yuehua, Dai Jingping, Zhang Qin, 2004. Electrochemical flotation of diethyldithiocarbamate-pyrrhotite system. J. Cent. South Univ. Technol., 11(3) 270 - 274 Janetski, N. D., Woodbum, S. I., Woods, R., 1977. An electrochemical investigation of pyrite flotation and depression. Inter. J. Miner. Process, 4 227 - 239 Jellinek, F., Poliak, R. A., Shafer, M. W., 1974. X-Ray photoelectron spectra and electronic structure of zirconium trisulphide and triselenide. Materials Research Bulletin, 9(6) 845-856... 

Vathsala, K. A. Natarajan, 1989. Some electrochemical aspects of grinding media corrosion and sphalerite flotation. Inter. J. Miner. Process, 26(3 - 4) 193 - 203 Walker, G. W., Stout, J. V. Ill, Richardson, P. E., 1984. Electrochemical flotation of sulphides reaction of chalcopyrite in aqueous solution. Inter. J. Miner. Process, 12 55 - 72 Wang Dianzuo, 1983. Structure and reactivty of organic depressant on flotation. Nonferrous Metals, (2) 47-51... 

Zhao Jing et al., 1988. Research on the mechanism of chalcopyrite depressed by sodium mercaptoacetic. Nonferrous Metals (part of mineral processing), (3) 42 - 45 Zhuo Chen and Yoon, R. H., 2000. Electrochemistry of copper activation of sphalerite. Inter. J. Miner. Process, 58 57 - 66... 

T. N. Khmeleva, W. Skinner, and D. A. Beattie, Depressing mechanisms of sodinm bisulphite in the coUectorless flotation of copper-activated sphalerite, Internat. J. Mineral Processing 76(1-2) (2005). 

Morris. G.E., Eomasiero. D.. and Ralston. J., Polymer depressants at the talc-water interface Adsorption isotherm, microflotation and electrokinetic studies, Int. J. Miner. Process., SI, 211. 2002. 

J. Shibata, S. Matsumoto, H. Yamamoto, E. Kusaka, and Pradip. Flotation separation of plastics using selective depressants. Int. J. Miner. Process., 48 (3-4) 127-134, December 1996. 

Fuerstenau, D. W, and Huang, R 2003. Interfacial phenomena involved in talc flotation and depression. XKII International Mineral Processing Congress. South African Instimte of Mining and Metallurgy in Marshalltown, Cape Town, South Africa. 1034. 

Pugh, R. J. 1989. Macromolecular organic depressants in sulfide flotation—A review, 2. Theoretical analysis of the forces involved in the depressant action. Int. J. Miner. Process. 25 131. 

Uses Mineral processing surfactant flotation depressant zinc sulflde depressant ... 

Other Interaction Processes. The selectivity of flotation reagents in a pulp and their functions depend on their interactions with the mineral phases to be separated, but other physicochemical and hydrodynamic processes also play roles. AH adsorption—desorption phenomena occur at the sohd—hquid interfacial region. Surface processes that influence such adsorptions include activation and depression. Activators and depressants are auxiUary reagents. 

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 Bureau of Mines, within the Department of the Interior, funds a substantial amount of chemical engineering research in its in-house laboratories, particularly in the area of hydrometallrugical separation processes. The U.S. minerals industry is currently in a depressed state typified by diminished research efforts within industrial laboratories and, in some cases, wholesale termination of research operations. As a result, new researchers have bleak prospects for industrial employment. At the same time, the United States cannot afford to lose a professional generation of research persormel in an area that would be of critical importance if foreign supplies of certain metals were interrupted. 

Several reviews on ore processing by flotation are available.17-21 In addition to providing details of the chemistry of collectors they describe the use of activators and depressants. The former usually convert the surfaces of an ore particle which does not bind strongly to conventional collectors to one that does. The addition of Cu2+ ions to enhance the flotability of minerals such as sphalerite, a zinc sulfide, has been exploited for some time.4 Formation of a surface layer of CuS has been assumed to account for this, but the mechanisms and selectivities of such processes continue to be investigated.18,22,23... 

This process meant the pressuring of coal, tars, and mineral oils by stages, into their final products. As to the gasoline in 1926 the decision was reached by the Vorstand that a large-scale experimental plant should be set up at Leuna for the production of 100,000 tons. We fell into the Depression and there were enormous technical difficulties. Within the Farben Vorstand, confidence in the process was seriously shaken. The whole Leuna plant was almost closed down. It was only the confidence of Bosch and Krauch and us technical men that was able to prevent this being done. We always had full confidence that technical difficulties would be overcome, and the future proved us right. 

The quality of the water in which the cassiterite flotation takes place is also highly important. Both ions found in process water supply and those generated by the minerals present in the pulp may affect the performance of the collectors as well as the surfaces of either cassiterite or gangue minerals by either depressing or activating them. 

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