| Adsorptive bubble separation is one of new rapidly developed separation techniques among the few decades. The paper studied the process of adsorptive foam separation for the recovery of Zn( II) ,Cu( II) in the solution by the guide of surface chemistry ,coordination chemistry and chemical transfer theory.The anion surfactant NaLS was the most efficient in the process and was selected as collector by orthogonal method. The interfacial tension and CMC of NaLS (CMC 6.5 × 10-3M) in the solution was measured by hanging ring test, The function relationship between interfacial tensions σ and NaLS concentration was: σ =-0.9523 In 2C-24.534 In C-81.411 .The relation of interfacial adsorption equilibrium in the solution system was respectively tested and calculated with Gibbs equation and dynamic method .The conclusion showed that (1) the experiment result of dynamic method with was highly in coordination with the value which from theoretical calculation. (2) The surfactant molecule was in arrangement of monomolecular layer at the gas-liquid interface.When NaLS was used as the collector in the process, the optimal conditions were the pH of feed solution 5.0-6.0,air flow rate 100ml/min,the liquid column depths 20cm, the surfactant concentration determined by its CMC and feed concentration. Under this condition, the 3 can be above 20.Also, the optimal pH (5.0) was calculated theoretically for the recovery of the Cu( II).On the basis of chemical transfer theory, the transfer mechanism was studied for the process of adsorptive bubble separation and the mathematical model describing the axis diffusion in continuous foam column and basic equation about the rate of mass transfer are set up. The results showed that the coefficient of eddy diffusion ( 5.21 × 10-5m /s ) was much greater than that of molecule diffusion (3.45 × 10-10 m /s) and the eddy diffusion ability of the solution in the bulk was much strongerthan their molecule diffusion ability in the liquid film...
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