Home – Home – Jornals – Journal of Structural Chemistry 2017 number 6

XPS, Pb L ₃ and Cu K EXAFS, solid state NMR, and EPR techniques are used to study insoluble products formed in the interaction of aqueous solutions of lead(II) nitrate and copper (II) sulfate with potassium n -butylxanthogenate (PX). The XPS spectra of lead xanthogenates with the composition PbX₂ are similar to those of PX, and interatomic distances of 0.279 nm suggest a nearly ionic character of Pb-S bonds. In copper xanthogenate precipitating together with dixanthogene (approximately 15 wt.%), the Cu(I)-S bond length is smaller (0.229 nm), and copper coordination number of 2.9 in a composite with dixanthogene increases to 3.3 after its removal by washing with acetone. The XPS spectra indicate the covalent character of the bond and non-equivalence of xanthogenate radicals. Solid state ¹H and ¹³C NMR spectra as well as the actual absence of metal lines under the measurement conditions demonstrate strong disordering of the structure of xanthogenates, which is stronger for PbX₂ and weakest in CuX after the removal of dixanthogene. EPR reveals sulfur-containing radicals and Cu²⁺ in CuX, however, their amounts are insignificant and decrease after the washing with acetone. The results of the work are significant for the understanding of the reactivity of xanthogenates, in particular, under the conditions of flotation beneficiation of base metal ores.