Research on the synergistic effect of sodium oleate and lauramidopropyl betaine on the reverse flotation separation of quartz and hematite: An environmentally friendly strategy

This research investigated the synergistic effect of an environmentally friendly combined collector (SLB) of lauramidopropyl betaine (LAB35) and sodium oleate (NaOL) on the separation process of quartz and hematite in reverse flotation. The results of microflotation experiments indicated that when the mass ratio of NaOL to LAB35 is 5:1, the recovery of quartz can be increased by 6.22 %. Further experiments with artificial mixed ores corroborated the findings. The foaming ability demonstrated that the incorporation of LAB35 induced a substantial increase in bubble density per unit area accompanied by a marked prolongation of bubble longevity, which collectively contributes to the reduced requirement for collectors. The presence of LAB35 compromised the bilayer adsorption architecture of NaOL while enhancing its chemisorption on quartz surfaces, thereby facilitating the enrichment of Ca-OOCR colloidal precipitates at quartz interfaces. Molecular dynamics simulations revealed that LAB35 increased the overlap degree between the oxygen density field of collector reagents and Si-O-Ca+ sites on quartz surfaces, which consequently amplified the electrostatic attraction at quartz-collector interfaces. This intensified interaction expanded the coverage area of the carbon density field from collector molecules, thereby elevating the probability of interfacial water molecular displacement from quartz surfaces. The collector LSB not only curtails chemical consumption in the flotation process, thereby reducing environmental pollution, but also enhances economic benefits.