HEADSPACE ANALYSIS GAS-PHASE INFRARED-SPECTROSCOPY - A STUDY OF XANTHATE DECOMPOSITION ON MINERAL SURFACES

The O-ethyldithiocarbonate (ethyl xanthate, CH3CH2OCS2-) anion is a wi dely used reagent in mineral processing for the separation of sulphide minerals by froth flotation. Ethyl xanthate interacts with mineral po wders to produce a hydrophobic layer on the mineral surface. A novel i nfrared technique, headspace analysis gas-phase infrared spectroscopy (HAGIS) has been used to study the in situ thermal decomposition produ cts of ethyl xanthate on mineral surfaces. These products include CS2, COS, CO2, CH4, SO2 and higher molecular weight alkyl-containing speci es. Decomposition pathways have been proposed with some information de termined from H-2- and C-13-isotope labelling experiments. (C) 1997 El sevier Science B.V.