The rapid development of industrial enterprises entails a significant increase in industrial wastes that poison the atmosphere and water bodies. One of the sources of pollution is wastewater from beneficiation plants. Their composition is complex and diverse, and therefore effective analytical control over the content of toxic substances in them has not been fully achieved.

The OP-4 reagent is an oxyethylated alkylphenol with an average degree of oxyethylation equal to 4, and is used in ore flotation. Various methods have been proposed for the quantitative determination of such surfactants. However, almost all of them were used for the analysis of either pure surfactants or relatively concentrated solutions. In this case, surfactants such as OP-7 and OP-10, which are well soluble in water and have a greater degree of oxyethylation, were usually determined, unlike OP-4.

The widespread use of various substances in the flotation of minerals pollutes wastewater, which, poisoning water bodies, poses a threat to the normal existence of wildlife.

Very small amounts of sulfides must be determined in natural waters, wastewater from concentrating plants and other enterprises. Evaporation of such solutions often changes their chemical composition and requires considerable time. ...