The effect of collectors on froth stability of frother: Atomic-scale study by experiments and molecular dynamics simulations

Abstract

The effect of sodium diethyldithiocarbamate (DDTC)/butyl xanthate (BX) on froth stability formed by methyl isobutyl carbinol (MIBC) was investigated using experiments and molecular simulations, and the mechanism of the effect of differently structured collectors on the interfacial water at the gas–liquid interface was discovered. The froth stability indicated that DDTC and BX could considerably reduce the solution surface tension, increase the froth half-life, and maximum froth layer volume compared with MIBC solutions. Particularly, in the BX-containing system, the froth half-life reached an astonishing 160 s, and the maximum froth layer volume reached 270 ml. To explain this observation, this study used molecular simulations to provide new insights into the interactions between DDTC/BX and MIBC and water at the molecular level. The results demonstrate that the density of water molecules at the interface of the DDTC/BX solution is higher than that of the MIBC solution, the orientation of water molecules at the interface is more ordered, and the hydrogen bonds are more tightly connected. The results are consistent with the experimental data, demonstrating that DDTC/BX improves the significance of MIBC on water molecule rearrangement at the gas–liquid interface. This study can offer a reference for studying the effect of collector structure on frother performance and can offer important guidance for the design of mineral flotation reagents.