Hollow fiber solvent extraction removal of toxic heavy metals from aqueous waste streams

Kinetic and dynamic study of liquid–liquid extraction of copper in a HFMC: Experimentation, modeling, and simulation

“…Shell side mass transfer coefficient depends on the hydrodynamics, geometry of the module, number of fibers, and the presence of baffle. In our case, we used the following correlation based on liquid-liquid extraction with various solutes and solvents for parallel flow without baffle 18 :…”

“…This can be justified as partition coefficient can be modified by various other factors such as pH, temperature, and type of diluent without changing the initial concentration of copper and oxime. For example, Yun et al 18 and Hu and Wiencek 35 studied the copper/LIX84-heptane and copper/LIX84-tetradecane system, Figure 9. Effect of partition coefficient on extraction dynamics of copper with LIX 84-I.…”

Integrated membrane process for gold recovery from hydrometallurgical solutions

“…To determine the rate-controlling step, we consider the commonly used hypothesis that the extraction involves four sequential steps: the effective rate of the interfacial reaction at surface, mass transfer from the bulk aqueous feed to the inside surface of the hollow-fiber membrane, diffusion across the membrane itself, and mass transfer into the organic solution surrounding the fiber. From the bulk-loaded organic LIX79 phase in the stripping module, the gold complex is transferred to the membrane-strip interface at the pore mouth, and finally transferred to the bulk aqueous stripping phase (Yun et al, 1993).…”

“…9, and k, is the effective rate of interfacial reaction at the surface: kf, k,, and k, are the mass-transfer coefficients in the aqueous feed, membrane, and the organic solvent, respectively; di, D,, and dl,, respectively, are the internal, external, and logarithmic mean fiber diameters. Equation 9 was derived to estimate the value of k j similar to the methods published in the literature (Yun et al, 1993;Yang et al, 1996Yang et al, , 2000. The first term on the righthand side of Eq.…”

“…In the present experimental conditions, N, , ranges from 5.5 to 8.2. Similarly, for the shell-side mass-transfer coefficient, the following correlation was given (Prasad and Sirkar et al, 1988;Basu et al, 1990;Yun et al, 1993) …”