Abstract
The effect of oxidative treatment on colloid-chemical properties of lignosulfonates was studied. Oxidation of lignosulfonates (403–423 K, $P_{O_2 } $ = 0.2–0.8 MPa, 0.5–1 h) is accompanied by a decrease in the content of hydroxy groups and by an increase in the content of carbonyl groups in oxidation products. Under severe oxidation conditions (423–433 K, $P_{O_2 } $ = 0.8 MPa, 3 h), lignosulfonates undergo chemical degradation with the formation of lower carboxy derivatives. The oxidized lignosulfonates exhibit lower performance, compared to the initial samples, in wetting and dispersion of sphalerite and elemental sulfur.