Using reagents in the form of inverse microemulsion for lead and zinc sulfide flotation

Abstract

The paper presents the results of studies on the use of collecting agents in the form of an inverse microemulsion (IМE) of the «water in oil» type (i.e. suspended water droplets are in the oil phase) for the flotation extraction of lead and zinc minerals. Lead and zinc concentrates, lead-zinc ore were used as initial samples for flotation. The content of galena in the lead concentrate was 74.7 %, and the content of sphalerite in zinc was 78.7 %. Basic collecting agents in the IМE composition were potassium butyl xanthate (PBX) and kerosene. A nonionic surfactant (NSA) was used for IМE stabilization. Casein was used as additives to main reagents to remove the negative effect of osmotic pressure during the IМE preparation. Casein was transformed into the active soluble form using sodium sulfide. The particle size in the inverse microemulsion was 12.38 nm. In flotation tests, the following options for feeding reagents to the flotation pulp were studied: IМE, IМE + frother, potassium butyl xanthate + frother. The T-92 reagent was used as a frother. PBX consumption as part of IME and in the traditional feeding was 26 g/ton. The results of laboratory tests showed that the method of feeding flotation reagents in the form of IМE leads to both an increase in the flotation rate of lead and zinc sulfides and an increase in their recovery into a foam product. In addition to the increased flotation speed, tests with the use of IМE in the bulk lead-zinc ore flotation cycle showed an increase in extraction into the ultimate concentrate by 10.8 % for lead, by 38.5 % for zinc, in comparison with the traditional feeding of reagents (collector + frother). An increased selectivity of the IМE effect in relation to zinc sulfides, in comparison with lead sulfides, was noted. The flotation rate coefficient of sphalerite is 7.8 times greater than that of galena. An increase in extraction into the ultimate zinc concentrate is also higher and amounted to 16.78 %, while for the lead concentrate it is 1.9 % under the same conditions.