Effect of drop size distribution on mass transfer analysis of the extraction of nickel(II) by emulsion liquid membrane

In the separation process using emulsion liquid membranes, the polydispersity affects mass transport of metal ions from the external phase because under steady operating conditions, drop size and size distribution are proportional to the interfacial area. The present study aims to assess the importance of polydisperse character of the emulsion globules. An advancing reaction front model considering emulsion globules of various sizes with same sauter mean diameter has been proposed for this purpose. In this paper, the important variables affecting sauter mean diameter of the emulsion drops, including injection method of emulsion, stirring speed, oil phase viscosity, composition of inner water phase and solute permeation rate are also systematically investigated. (C) 2003 Elsevier B.V. All rights reserved.