학술논문
Membrane extraction for separation of copper cations from acid solution using polypropylene hollow fibre membrane
Document Type
Article
Author
Source
Polymers for Advanced Technologies; October 2005, Vol. 16 Issue: 10 p738-743, 6p
Subject
Language
ISSN
10427147; 10991581
Abstract
The membrane extraction of copper ions was carried out using hydrophobic poly(propylene) (PP) hollow fiber membrane modules and kerosene solutions containing organic extractant. The influences of different extractant on the extraction yield, mass transfer performance and mass transfer mechanism were studied. Compared with 2‐ethylhexyl phosphoric acid (2EHPA) and 2‐methyl‐5‐sulpho benzaldoxime (2M5SB), di‐(2‐ethylhexyl)phosphoric acid (D2EHPA) extractant system with high distribution coefficient exhibited higher extraction yield of 99.7%. The extraction equilibrium time, the final extraction yield and the total mass transfer coefficient were independent of the flow rates of two phases. The extraction equilibrium time and the final extraction yield at different flow rates of two phases were 80 min and near 99.5%, respectively. A mass transfer model of a complexation reaction describing the overall mass transfer resistance was controlled by interfacial reactions rather than the aqueous and organic boundary layer which could explain the effect of flow rate on the final extraction yield and the total mass transfer coefficient. This model showed that the mass transfer resistance and mass transfer coefficient were independent of Cu2+when copper ion concentration was more than 0.06 g/L. However, when copper concentration was less than 0.06 g/l, the mass transfer resistance increased as Cu2+concentration decreased, and the mass transfer coefficient decreased as Cu2+concentration decreased. Extractant entrainment in the aqueous phase and membrane fouling were investigated primarily. It was found that the solvent entrainment could reduce to 10 ppm much lower than 200 ppm of the classic liquid–liquid extraction, and that the cleaning of contaminated membranes was not complete. However, it can be still concluded from this research that the membrane extraction in PP hollow fibre with D2EHPA extractant would be an effective and promising processing means for Cu2+separation from aqueous solution. Copyright © 2005 John Wiley & Sons, Ltd.