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South African Journal of Science

versão On-line ISSN 1996-7489
versão impressa ISSN 0038-2353

S. Afr. j. sci. vol.103 no.3-4 Pretoria Mar./Abr. 2007

 

RESEARCH LETTER

 

Dithiocarbonate and trithiocarbonate interactions with pyrite

 

 

J.A. Venter; M.K.G. Vermaak

Department of Materials Science and Metallurgical Engineering, University of Pretoria, Pretoria 0002, South Africa

 

 


ABSTRACT

Dithiocarbonate (xanthate) collectors have been the workhorse of the sulphide flotation industry for more than 80 years. More recently, some flotation plants have started to use a new collector, trithio-carbonate (TTC). Extensive research has been conducted on the interaction of different substrates with xanthates, which adsorb electrochemically and are present as a chemisorbed xanthate, metal xanthate or dixanthogen. The work reported here is the first detailed, fundamental evaluation of a long-chain trithiocarbonate collector for sulphide minerals. The results show that this collector-unlike the widely used xanthate collector-has a strong non-electrochemical collection action in addition to an electrochemical one. The non-electrochemical action opens up significant possibilities of changing mill conditions (specifically regarding the propensity of sulphide minerals to oxidize), to obtain better sulphide recovery.


 

 

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Received 1 June
Accepted 30 September 2006.

 

 

* Author for correspondence. E-mail: albert.venter@eng.up.ac.za

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