Two-dimensional correlation analysis of continuous online in situ ATR-FTIR on the adsorption of heptyl xanthate at the surface of ZnS and Pb(II) activated ZnS

Abstract

Zinc sulfide (ZnS) is an important and widely used semiconductor material. To improve the flotation efficiency of zinc minerals and explore corresponding mechanisms has been a central topic of flotation technology and flotation chemistry. ZnS with a high purity and a large surface area was synthesized using zinc nitrate as a zinc source and sodium sulfide as a sulfur source in the laboratory. The synthetic ZnS was then activated with lead nitrate in order to understand involving mechanism and consequently improve its flotation efficiency with xanthates. The adsorption of heptyl xanthate (KHX) at the surface of ZnS and Pb(II) activated ZnS were examined as a function of time using continuous online in situ attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. The two-dimensional IR correlation analysis indicates that lead xanthate and zinc xanthate coexisted on the Pb(II) activated ZnS surface and lead xanthate formed prior to zinc xanthate at the surface of Pb(II) activated ZnS. The activation by lead ions increased the adsorption amount and rate constant of KHX. The KHX adsorption onto both ZnS and Pb(II) activated ZnS obeys the pseudo first order kinetic model and the desorption with deionized water is negligible after 20–30 min.