改性金属膜膜萃取萃铜速度影响因素考察

STUDY ON THE COPPER TRANSFER RATE IN MEMBRANE EXTRACTION WITH MODIFIED METALLIC MEMBRANE

针对有机中空纤维膜材料在膜萃取过程中出现膜孔溶胀的问题，采用聚四氟乙烯涂敷在不锈钢纤维烧结膜表面制备一种有机／无机复合膜并用作膜萃取的支撑材料，在平板式膜器中进行萃铜研究．考察了影响铜的萃取及反萃过程传质速度的主要因素，包括料液浓度、水相及有机相流速等，并根据试验结果初步探讨了膜萃取过程传质阻力的分布情况，结果表明有机相边界层阻力大于水相边界层阻力．

Hollow fiber membranes may cause pore dissolution and shape change in membrane extraction process, and it is a serious problem for industrial use of this technology. To solve this problem, a layer of teflon was coated on the surface of stainless steel fiber sintered membrane to get a sort of organic/inorganic composite membrane. And this new membrane material was used as support in a plate membrane extraction module for recovery of copper from low concentration solution. The effects of process variables, including flow rate of aqueous and organic phase, concentration of copper in aqueous feed and extractant in organic phase, on copper transfer rate of extraction and stripping process are studied in this paper. The mass transfer resistance of extraction and stripping processes is also discussed. The results show that the resistance of organic boundary is more important than that of aqueous phase boundary in the overall resistance of extraction and stripping processes.