The effect of diethylenetriamine (DETA) on the formation of Cu2+-, Ni2+- and Fe3+-amyl xanthate ion (AX(-)) complexes was studied by UV spectroscopy. The absorption spectra of solutions containing metal ions (Mn+) and AX(-) or Mn+ and DETA were studied to determine the lambda(max) and, when possible, the molar absorptivities of the species in solution. In the Cu2+ and Ni2+ systems, the change in the absorption bands of the M2+-AX(-) complex and/or AX(-) when DETA was added to solutions of fixed M2+/AX(-) ratios was used to propose a reaction scheme. DETA was shown (1) to dissolve M(OH)2 and (2) to suppress the formation of M(AX)(2) depending on the M2+/AX(-) ratio. DETA dissolves Cu(OH)(2) instantaneously and quantitatively whereas the dissolution of Ni(OH)(2) by DETA is very slow. While the formation of Ni(AX)(2) is dependent on the M2+/AX(-)/DETA ratio, the formation of Cu(AX)(2) was not affected significantly by the solution composition. The M(AX)(2) self-reduction products, CuAX and NiAX isolated from solutions containing M2+, AX(-) and DETA were characterized using atomic absorption and FT-IR spectroscopy. Fe3+ behaves differently than Cu2+ and Ni2+ with AX(-) and/or DETA. Even in the presence of a large excess of AX(-) and/or DETA, Fe3+ exists almost exclusively as Fe(OH)(3) at a pH of 9.3. DETA decreases the amount of Fe3+-AX(-) complex in solution. (C) 2004 Elsevier Ltd. All rights reserved.