FFECT OF DIETHYLENETRIAMINE ON XANTHATE INTERACTION WITH PB-CONTAMINATED PYRITE

Xanthate interaction with pyrite in the presence of Pb and diethylenet riamine (DETA, NH2-CH2-CH2-NH-CH2-CH2-NH2) was investigated by cyclic voltammetry, open-circuit potential measurements, an ex-situ spectroel ectrochemical technique, and zeta potential measurement. Uptake of xan thate was promoted by the presence of Pb. The only xanthate product de tected was dixanthogen. Xanthate adsorption on Pb-contaminated pyrite was suppressed by DETA, but relatively large concentrations were requi red. Addition of DETA decreased the open-circuit potential and increas ed the zeta potential in the absence or presence of Pb ions, indicatin g adsorption of DETA. The mechanism of depression of DETA may be a com bination of competition with xanthate for adsorption sites and creatio n of reducing conditions which retard oxidation of xanthate to dixanth ogen; (C) 1998 Published by Elsevier Science Ltd. All rights reserved.