Study On The Separation Of Y～(3+) By Foam Flotation From The Dilute Solution

Foam flotation separation is based on the different Gibbs interface adsorption. The surface tension of the surfactants in the flotation was tested. From the relation between surface tension and concentration, the limit area of a molecular was calculated using the Langmuir formula, and the result was found that the surfactant was exactly erect in the foam surface, because the area Am of SDS SDBS SLS was 0.47nm 0.21nm 0.28nm2 at 298K and the area Am of SLSwas 0.30nm2 at 303K.In the following study, the surfactants foams stability was tested, the tolerance norms about the foams stability were searched to compare the different surfactants. The study showed that the slope-compared was the easier way than the classics. The netted structure model was advanced in the experiments for the foams stability enhanced when the Y3+ was added. The hexagon foam was the most stable by the theory counting, which was proved by the experiments.The Y3+ separated from the dilute solution by the foam flotation was studied in this paper. The technological conditions of separating Y3+, such as pH, ionic strength, airflow velocity, surfactant concentration et al were studied using orthogonal design and optimum technological conditions were obtained, pH=5.0, ionic strength 1.0 X 10-3mol dm-3, airflow velocity 15cm3 s-1, surfactant concentration 5.0 X 10-3mol dm-3 under the optimum technological conditions, the separation rate will be greater than 98.98%.The dynamical equation showed that the reaction was the one grade, the experiment data well agreed with the theoretical study. All these results explained that the surface and airflow velocity were the decisiveness factors, the interaction of a surfactant with oppositely charged ion and the ion-pair expanding in solution or at solution-gas bubble interface was the key in the foam flotation.The results showed that the separation Y3+ was feasible by foam flotation.In the course, the surfactant SLS was the best, the R could get above 98.8%. The foam flotation was greater latent capacity than the classic separation way for it's operation easier, lower investment and consumption, which will be the new way to separate the rare earth, the meaning of the foam flotation is obviously great.