Abstract <p>A lignosulfonate (LS) sample was modified by introducing zinc and iron(III) cations in it (ion exchange sorption). Associative and dissociative transformations of modified LSs in an aqueous environment were studied. The effects of the concentration (0.01–0.32 g/dm³) and nature of the counterion (Na⁺, H⁺, Zn²⁺, Fe³⁺) in LS on the variation of pH, specific and molar electric conductivity, size of LS associates, and their polydispersity, as well as the surface tension at the liquid–gas boundary, were revealed. Using the nanoprecipitation method, modified LS nanopowders with particle sizes of 40–250 nm were obtained. It is shown that the nature of the LS cation introduced in the polymer matrix has almost no effect on the morphology and size of the isolated nanostructures. The encapsulating effect of the obtained nanoassociates of modified LSs relative to the hydrophobic dye cerasine red was evaluated. It was found that the encapsulation efficiency increases with the growth of LS concentration and the charge introduced in the LS cation and amounts to 60–70%.</p>