Separation of a mixture of rare earth fluorescent powders by two-liquid flotation using polar and non-polar organic solvents for recycling

The general conclusion of this work is that the two-liquid flotation using organic phases is an effective method to separate fluorescent powders. After selecting suitable non-polar and polar solvents (i.e. n-heptane and DMF), the effect of surfactant concentration was investigated. Then, the two-stage two-liquid flotation was carried out. In the first stage, the green powder was separated in the presence of DAA (2 times 10^-4 mol L^-1) whereas in the second stage, the blue powder was separated from red powder; in the presence of sodium 1-octanesulfonate (20 times 10^-4 mol L^-1).