Siberian Federal University

The composition and structure of saponins, which belong to the group of terpenoids – substances present in the extractive part of wood after delignification are considered in the article. The carbohydrate part of lignosulfonates from the sulfite delignification method contains the monosaccharide L‑rhamnose, as a component of saponins that have foaming properties, which has been determined by thin‑layer chromatography method. It has been established that the lignosulfonate produced by the sulfite method has the greatest foaming capacity, in contrast to the neutral‑sulfite lignosulfonate. The foaming agent, for which it is proposed to use sulfite lignosulfonate, is necessary for the flotation process of minerals from the composition of natural ores. The contact angles in the «water – foaming agent – mineral» system were measured using the “sessile droplet” method with the use of the “Compass‑3D” program to substantiate the use of lignosulfonate as a foaming agent and collector in the composition of a flotation agent. The relative values of the work of adhesion Wadg were calculated for assessing the efficiency of the process of adhesion of a mineral particle to the wall of a foam bubble during flotation. It has been shown that the work of adhesion for sulfite lignosulfonates will be maximum, since the wetting angle reaches 89–90°. This characteristic is halved for neutral‑sulfite lignosulfonates, where the contact angle does not exceed 30°, and the content of the monosaccharide L‑rhamnose (hexosan class) in the hemicelluloses of the carbohydrate part is minimal. This substantiates the possibility of using sulfite lignosulfonates as foaming components of domestic flotation systems for extracting minerals from natural ores