Application of electrochemical kinetics to elucidate the leaching mechanism in the bio-oxidation of a synthetic nickel sulphide

dc.contributor.author	Huberts, Robert
dc.date.accessioned	2015-02-06T06:56:15Z
dc.date.available	2015-02-06T06:56:15Z
dc.date.issued	2015-02-06
dc.description.abstract	The importance of the direct and indirect mechanisms in the bacterial leaching of a synthetic nickel sulphide is investigated using an electrochemical leaching model. Sterile controls runs, in which only ferric leaching took place, are compared with runs in the presence of an active, adapted bacterial culture. The direct mechanism occurs when bacteria attach to the sulphide mineral and catalyze the oxidation of the mineral, presumably with enzymes (biological catalysts). No evidence was found of the direct mechanism, in fact ferric leaching appeared to be inhibited as the bacterial presence increased due to growth. Considering evidence obtained by the fitting of the electrochemical model, it is tentatively suggested that leaching of the mineral is largely due to chemical ferric leaching, with the leaching role of bacteria restricted to re-oxidizing the resulting ferrous ions. Whether this is the case for other minerals remains to be established.	en_ZA
dc.identifier.uri	http://hdl.handle.net/10539/16901
dc.language.iso	en	en_ZA
dc.subject.lcsh	Nickel sulphide
dc.subject.lcsh	Leaching
dc.title	Application of electrochemical kinetics to elucidate the leaching mechanism in the bio-oxidation of a synthetic nickel sulphide	en_ZA
dc.type	Thesis	en_ZA