Study on a Novel Disphase Supplying Supported Liquid Membrane for Transport Behavior of Divalent Nickel Ions

Abstract

A novel disphase supplying supported liquid membrane (DSSLM), containing supplying feed phase and supplying stripping phase for transport behavior of Ni(II), have been studied. The supplying supported feed phase included feed solution and di(2-ethyhexyl) phosphoric acid (HDEHP) as the carrier in kerosene, and supplying stripping phase included HDEHP as the carrier in kerosene and HCl as the stripping agent. The effects of volume ratio of membrane solution to feed solution (O/F), pH, initial concentration of Ni(II) and ionic strength in the feed solution, volume ratio of membrane solution to stripping solution (O/S), concentration of H2SO4 solution, HDEHP concentration in the supplying stripping phase on transport of Ni(II), the advantages of DSSLM compared to the traditional supported liquid membrane (SLM), the system stability, the∼reuse of∼membrane∼solution and the retention of membrane phase were studied. Experimental results indicated that the optimum transport of Ni(II) was obtained when H2SO4 concentration was 2.00 mol·L−1, HDEHP concentration was 0.120 mol·L−1, and O/S was 4: 1 in the supplying stripping phase, O/F was 1: 10 and pH was 5.20 in the supplying feed phase. The ionic strength in supplying feed phase had no obvious effect on transport of Ni(II). When initial Ni(II) concentration was 2.00×10−4 mol/L, the transport percentage of Ni(II) was up to 93.1 % in 250 min. The kinetic equation was deduced in terms of the law of mass diffusion and the interface chemistry.