A.A.Taha*, A.M. Ahmed, A.A. Bayoumy

Department of Chemistry, Faculty of science, University of Alexandria, Alexandria, Egypt

Received 2 September 2002; accepted in revised form 19 August 2003

Abstract

The rate of mass transfer was studied at (i) a single horizontal cylinder cathode and (ii) a vertical array of closely spaced horizontal cylinders and an array of separated cylinders. The mass transfer coefficients were obtained by measuring the limiting current of the cathodic reduction of alkaline potassium ferricyanide. Variables studied were: cylinder diameter, physical properties of the solution, and nitrogen flow rate. The mass transfer coefficient was found to increase with increasing nitrogen superficial velocity. Decreasing the diameter was found to increase the mass transfer coefficient. The mass transfer data were correlated by the following equations:

For single horizontal cylinder cathode: J = 2.138 (Re. Fr)^-0.24

For an array of separated cylinders: J = 100 (Re.Fr)^-0.28

Possible practical application of gas sparged array of horizontal cylinders in building electrochemical reactors are discussed.

Keywords: Mass transfer, horizontal cylinders, gas sparged, electrochemical reactor.

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* Corresponding author. E-mail address: ghada_113@hotmail.com