SOLUTION INTERACTION OF ETHYL XANTHATE AND SULFITE AND ITS EFFECT ON GALENA FLOTATION AND XANTHATE ADSORPTION

The solution interaction of ethyl xanthate and sulphite has been studi ed by UV spectroscopy. The rate of ethyl xanthate decomposition and fo rmation of an intermediate compound, ethyl perxanthate, has been measu red as a function of sulphite concentration, temperature and purging g as. The reaction mechanisms are discussed, with particular emphasis on the role of sulphite in the decomposition of ethyl xanthate and ethyl perxanthate. The regulating effect of ethyl xanthate decomposition by sulphite on ethyl xanthate adsorption on galena is also investigated. A mechanism involving simultaneous ethyl xanthate decomposition and a dsorption is proposed to partially explain galena flotation response i n the presence of sulphite solution species. The solution interaction of sulphite with xanthate is effectively controlled, allowing the spec ific effects of sulphite modification of galena surfaces to be more cl early discerned. (C) 1997 Elsevier Science B.V.