The search for effective reagents for the flotation of non-ferrous metals from mineral raw materials is an actual problem. The article discusses the results of research on improving the technology of processing copper–molybdenum ores using a combined collector emulsion. The object of research was copper–molybdenum ore containing 0.43% copper and 0.0089% molybdenum. Copper minerals are represented by chalcopyrite 1.2% and chalcocite 0.015%, while covellite is present in a much smaller amount. The main mineral of molybdenum is molybdenite. The cycle of collective copper–molybdenum flotation includes the main flotation, control flotation, and three re-cleanings of concentrate. In the basic mode, the collective Cu–Mo concentrate was produced with the copper content of 16.25% with an extraction of 77.79% and with the molybdenum content of 0.45% with an extraction of 79.38%. Reaflot, thionocarbamate, and butyl xanthate were used in a ratio of 1:3:15 to prepare a combined collector agent. In order to produce the combined collector emulsion, the best degree of dispersion, which amounted to 99.5% of particles with a size of −3.6 μm, was chosen. During the Cu–Mo ore flotation using an optimally dispersed microemulsion of the combined collector agent, a collective Cu–Mo concentrate was obtained with a copper content of 18.2% with an extraction of 83.58%, and with a molybdenum content of 0.49% with an extraction of 88.46%. The use of a combined collector agent increases the extraction of copper into the collective Cu–Mo concentrate by 5.79%, while the extraction of molybdenum increases by 9.08%.

A complex processing variant for pyrite cinders, i.e., the technogenic waste generated in the production of sulfuric acid, was proposed. This method provided preliminary chemical activation of the initial raw materials that comprised thermal treatment with a sodium bicarbonate solution and resulted in structural and phase changes of separate minerals. Due to chemical activation, it was possible to separate the nonferrous metals into separate products (in addition to the partial extraction of iron) and then concentrate the noble metals in the residue. The noble metals were then able to be extracted through a leaching process with a complex reagent based on sulfur compounds and subsequent cementation with zinc dust. The developed method, unlike pyrometallurgical methods, is less energy-consuming and more easily implemented than the known hydrometallurgical variants, enabling the separation of nonferrous metals and the partial separation of iron into separate middlings at the first stage. Noble metals are concentrated in the residue and extracted from it.

The Shalkiya deposit lead-zinc ore flotation processing regimes were developed with application of regrinding and apolar reagent based on oil and diesel fuel. An optimal ore grinding flow sheet was proposed, including feed grinding prior to flotation to 80 % of –0.074 mm size fraction, regrinding of the first lead cleaning cycle froth product to 97 % of –0.074 mm size fraction and scavenging lead flotation cycle tail — to 99 % of –0.074 mm size fraction. The Kumkolskoye deposit oil and diesel fuel mixed in the ratio of 1 : 1 was used as apolar reagent. It is shown that application of regrinding and apolar reagent, if compared with the plant established regime, permits to increase zinc content in zinc concentrate by 3.83 %, and zinc recovery — by 9.42 %; lead content in lead concentrate is increased by 5.18 %, and its recovery — by 12.36 %. With that, lead content in flotation tail decreases from 0.87 to 0.5 %, that of zinc — from 1.42 to 1.0 %, i.e., losses of lead and zinc in flotation tail are decreased by 20.07 and 10.29 %, respectively.

The article discusses the production of flotation reagents based on domestic sulfur-containing oil products using the ultrasonic cavitation method. Particular attention is paid to the selection of oil products based on the analysis of their qualitative and quantitative composition. Mercaptans (thioalcohols) are known to be the most effective sulfhydryl collectors. This study utilizes sulfur-containing oil products with the same sulfur content but differing in the form of sulfur presence in the starting materials: refined oil, mercaptan-containing product, and an intermediate product obtained during oil demercaptanization. Compositions were developed using these oil products and butyl xanthate. During ultrasonic cavitation, the dependence of emulsion stability over time on ultrasonic power and component ratios was determined. Optimal conditions for ultrasonic cavitation and the appropriate proportions of components in the compositions were established. Despite having the same sulfur content, it was found that only sulfur-containing products with specific structural characteristics are suitable for flotation reagent production. Additionally, ultrasonic cavitation's role in modifying the compositions' properties was identified, significantly influencing their efficiency as collectors.

This study investigates the effect of composite sulphur-containing collectors on the efficiency of floating hard-to-beneficiate sulphide polymetallic ores from the Tishinsky deposit (Kazakhstan). Specifically, this study examines a sulphur-containing collector comprising a sulphur-containing product and refined oil, as well as mixtures of these with sodium butyl dithiophosphate and sodium butyl xanthate in various mass ratios. This approach allows us to assess the role of oil-containing phases as carriers of hydrophobicity in colloidal–chemical interactions between flotation reagents and the mineral surface. The results of single-mineral flotation indicated that using a composite collector ([CO2SR]:[BX]:[BTP] = 1:1:1) provides higher flotation activity compared with conventional butyl xanthate. The most significant increase in recovery was observed for chalcopyrite and galena, indicating the selective nature of the reagent’s action. During the flotation of polymetallic ores, it was established that using the developed reagent system causes the lead content to increase by 4.35% (from 7.09% to 11.44%), whilst recovery rises by 5.67% (from 87.53% to 93.20%). For zinc, the increase in content reaches 5.13% (from 49.82% to 54.95%), whilst recovery increases by 12.9% (from 64.19% to 77.18%).