Two types of novel anti-corrosive ceramic internals have been designed for extraction of lithium and rare earths, and their hydrodynamic performance was investigated. 2. Holdup of hybrid ceramic internal was higher than that of ceramic plate by around 50%. Correlations were proposed to predict holdup for both types of internal with AARD of 5.9% and 9.3% respectively. 3. Sauter mean diameter of hybrid ceramic internal is smaller than that of ceramic plate by around 30%. Correlations were proposed to predict d 32 with AARD of 13.6% and 4.2% respectively.

Mechanical agitation or pulsation is usually introduced to a solvent extraction column to improve the efficiency. Recently a number of industrial scale pulsed disc and doughnut (PDD) solvent extraction columns have been found to have higher extraction efficiency while running with non-pulsing. In this study, the mass transfer performance of a PDD column was measured under pulsing and non-pulsing conditions using a 72.5 mm diameter disc and doughnut column. The effects of pulsation intensity and dispersed and continuous phase velocity on the mass transfer performance have been investigated. The results show that, under non-pulsing conditions, the overall mass transfer coefficient increased with increasing continuous phase flow rate and slightly decreased with increasing dispersed phase flow rate. With increasing pulsation intensity, the overall mass transfer coefficient decreased at first and then increased. Two correlations are proposed to predict the height of mass transfer unit and overall mass transfer coefficient in a PDD column including pulsing and non-pulsing conditions.

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Two types of novel anti-corrosive ceramic internals, the hybrid ceramic internal and ceramic plate, are designed and tested under pilot conditions for future industrial application in lithium extraction from salt lake brine. A standard liquid-liquid system with medium interfacial tension, 30% TBP in Shellsol 2046-water with acetic acid as solute, is used to test axial dispersion and mass transfer parameters, which are important to determine height of extraction columns, over a range of operating conditions. Results show that the hybrid ceramic internal has 50% lower axial dispersion coefficient and 50% higher mass transfer coefficient, both contributing to better mass transfer performance. Under proper operating condition, height of transfer unit of hybrid ceramic internal can reach as low as around 0.2m, which shows very good efficiency and makes it promising to be applied in the near future.