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Abstract: The use of Taylor–Couette flow for extraction by emulsion liquid membranes has been characterized. In particular, the rate limiting step for the extraction of a weak acid (benzoic) in an aqueous continuous phase to a strong base (NaOH) in the encapsulated internal phase has been attributed to a surfactant resistance. Numerical and analytical solutions are developed to characterize the mass transfer at Biot numbers . It is demonstrated for fixed droplet composition that a single curve exists for all for the extent of extraction by stretching the time coordinate by a function of the rotation rate that is proportional to the globule external area per unit total volume. Moreover, the leakage rate is shown to increase as and to be proportional to , the Kolmogoroff eddy velocity. Comparison with stirred tank data demonstrates that greater droplet stability exists for Taylor–Couette flow. [Copyright &y& Elsevier]