Selective removal of zinc using tri ethanolamine b 2016 Desalination and Wat

This work is a comprehensive study on the selective removal of Zn (II) from aqueous solution using a flat-sheet polypropylene-supported liquid membrane system. Tri-ethanolamine (TEA) dissolved in cyclohexanone was used as a carrier for the extraction of zinc ions through the supported liquid membrane. Different parameters affecting the zinc ion transport were studied. The experiments were performed at various operating conditions such as metal and acid concentration in the feed phase, strip phase concentration, and carrier concentration, to find the best set of parameters that would yield the maximum extraction. The extraction time, flux value, the stoichiometry of the complex formed, and membrane stability were also investigated. The experiments were performed in co-transport mode. The optimized conditions obtained for zinc ion transport are as follows: 2.30×10−4 mol/dm3 of Zn2+ ions and 1 M of HCl in the feed solution, 50% TEA in cyclohexanone in the membrane phase, and 0.7 M of NaOH in the stripping phase. Under these optimum conditions, the membrane is stable for about 10 consecutive experiments. The extraction efficiency was found to be 87% in 120 min.