Further studies on solvent extraction with immobilized interfaces in a microporous hydrophobic membrane

Novel liquid‐in‐pore configurations in membrane solvent extraction

“…Figure 4 shows also the data for NMP in the pore with two Celgard membranes. The value of k,,,,, obtained is 3.58 x cm2/s, we obtain a reasonable 7 , value 2.97 for the Celgard 2400 film (Prasad et al, 1986;Prasad and Sirkar, 1987a). Similar experiments with n-heptane in the pore reproduce results of Prasad and Sirkar (1987a Prasad and Sirkar (1987b) studied composite membranes using a sandwich of a hydrophobic membrane with organic in the pore and a hydrophilic membrane with aqueous in the pore.…”

“…This nylon film is highly porous with very large pores and appeared significantly compressible. With a slight reduction in 6, during experiments, T , would be around 1.1-1.2, a range observed with highly porous large pore membranes (Prasad et al, 1986).…”

“…Dispersion-free solvent extraction has been investigated recently using microporous membranes in different forms and wetting characteristics (Kiani et al, 1984;Prasad et al, 1986;D'Elia et al, 1986;Sirkar, 1987a,b, 1988;Dahuron and Cussler, 1988;Basu et al, 1990). In hydrophobic microporous membranes, the organic phase wetted the pores; and the aqueous phase, excluded from pores, was maintained at a higher pressure to immobilize aqueous-organic interfaces at pore mouths.…”

Modified correction-factor analysis of solvent extraction in rectangular membrane modules

“…Further, there has to be a density difference between the aqueous and the organic streams. A new dispersion-free microporous membrane-based solvent extraction technique (Kiani et al, 1984;Prasad et al, 1986) has been developed. In addition to the limitations mentioned above, this technique also overcomes several other limitations of conventional liquid extraction, such as the need for intimate mixing to form emulsions of the two phases, the limitation on independent phase flow rate variation and inability to handle particulates.…”

Integrated membrane process for gold recovery from hydrometallurgical solutions

“…In the present system both conditions are fulfilled, as NRe ranges from 3.0 to 11.0 and + = 0.35, and the notations D, = hydraulic diameter, D, = diffusion coefficient of solute in the tube side; d, = inner fiber diameter; L = fiber length; D, = diffusion coefficient of solute in the shell side; v, and us are the velocity of the liquid in the fiber side and the shell side, respectively. An estimate of the membrane masstransfer coefficient can be determined by the following equation (Kiani et al, 1984;Prasad et al, 1986):…”