Emulsion liquid membrane for lead removal: intensified low shear extraction

The paper provides a technological innovation process to improve lead removal under low shear counter rotating Taylor-Couette column (TCC). Emulsion was prepared using TOA, Span 80, kerosene, and ammonia. Feed solution composed of lead nitrate in deionised water and HCl. The emulsion and feed solution were then contacted in TCC at various conditions including HCl concentration, initial feed concentration, volume ratio of emulsion to feed phase, extraction time, and ratio of angular frequency of outer and inner cylinders. The results showed that the system was effective for lead removal. The best extraction performance was obtained at HCl concentration of 0.1 M, initial feed concentration of 40 ppm, volume ratio of emulsion to feed phase of 1/5, extraction time of 7 min, and angular frequency ratio of 0.5. Overall, the use of low-shear TCC process intensified the mixing of emulsion and feed phases well that avoiding emulsion instability during the process.