Organic depressant

Modifiers in the flotation of sulphide minerals mainly include depressants and activators. A depressant is defined as a reagent which inhibits the adsorption of a collector on a given mineral or adsorbed on the mineral to make the siuface hydrophilic, and includes inorganic depressants such as lime, sodium cyanide, sulphin dioxide, zinc sulphate, sodium sulphide etc., and organic depressants such as sulfhydryl acetic acid, polyacrylamide polymers containing various functional groups etc. In this chapter, roles of depressants in the flotation sulphide minerals will be discussed and some new organic depressants will be introduced. 

Depression of Mannatite and Pyrrhotite by Thio-Organic Depressants... 

The depressing property of the organic depressant mainly depends on its structure. Some quantitative criteria have been used to determine the depressing ability of the organic depressants (Wang, 1982, 1997). The characteristic index of an organic depressant is defined as follows ... 

Lin, Q., Jin, H., Wang, D., 1991. Preparation of some new micromolecular organic depressant and their reactivity. Journal of Central-South Institute Mining and Metallurgy, 3(22) 256 - 262 (in Chinese)... 

Liu Runqing, Sun Wei, Hu Yuehua, Xiong Daoling, 2006. Depression mechanism of small molecular mercapto-organic depressants on flotation behaviour of complex sulphides. Chinese Journal of Nonferrous Metals, 16(4) 746 - 751 (in Chinese)... 

Sun Wei, Liu Runqing, Hu Yuehua, 2005. Research on depression mechanism of jamesonite and pyrrhotite by organic depressant DMPS. Mining and Metallurgical Engineering (in Chinese)... 

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... 

Xu, B. and Huang, K., 1995. Role of a-amino aryl phosphorated organic depressant in flotation of high nickel matte. Nonferrous Metals, 1(47) 21-23 (in Chinese)... 

The structural characteristics of organic depressants may be summarized as follows the molecule must have as a small hydrocarbon framework as possible with several (over two) polar groups the polar groups located anywhere at the two ends a fraction of the... 

Organic depressants for Fe " -activated wolframite and quartz Depression of wolframite-quartz flotation with various flotation agents is shown in Figs. 5.16a and 5.16b. Experimental results for the concentration of the reagents for good depression of the above two minerals are listed in Table 5.22. The structural characteristics of the depressant molecules can be summarized as follows ... 

Patients with hypothyroidism and organic depression may need both levothyroxine and antidepressant drug therapy, in ievothyroxine-treated patients with hypothyroidism who were treated with sertraiine, there was an eievated serum thyrotropin concentration, indicative of a decrease in the efficacy of ievothyroxine. What is the possible mechanism of interaction between the two drugs ... 

Disability has heen traditionally associated with mental retardation, extreme mental illness, visual or hearing impairment, physical illness, or injury that affects an individual s mohihty, daily functions, and self-sufficiency. However, according to the World Health Organization, depression is the leading cause of disability (as measured by years lost due to disability), and the fourth leading contributor to the global burden of disease. 

Micromolecule Organic Depressant 4.2.1 Carboxylic Acids and Hydroxy Acids... 

Other macromolecule organic depressants consist of various algaes and alginates. Alginate can also be used as emulsifier. The structure of alginate is similar to that of cellulose. The structure of alginate is as follows ... 

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. 

Depression and anxiety disorders are common forms of mental illness. According to the World Health Organization, depression affects approximately 120 million people worldwide. In 2008, the National Institute on Mental Health (NIMH) reported that... 

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