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The liquid–solid mass transfer behavior of 8 cylindrical blade impeller it can act as electrode or catalyst support in a new stirred tank reactor was studied in relation to catalytic and electrochemical reactor design by the electrochemical technique which involved measuring the limiting current of the cathodic reduction of K 3 Fe(CN) 6 . Variables studied were blade length, impeller rotation speed, physical properties of the solution, effect of baffles, effect of immiscible liquids, effect of superimposed solution flow (continuous operation), effect of the distance between successive impellers in case of multi-impeller reactor and the effect of drag reducing polymers. The mass transfer data for single rotating impeller were found to fit the following equation: S h = 0.429     S c 0.33     R e 0.42 Superimposed solution flow and impeller separation were found to have little effect on the rate of mass transfer, baffles were found to increase the rate of mass transfer while the presence of immiscible liquid decreases the rate of mass transfer. Addition of drag reducing polymers (Polyox WSR-301) was found to reduce the rate of mass transfer at single impeller by a maximum of 15.8%. Examination of heavy metal removal from dilute solutions revealed that the rate of metal deposition agrees fairly with the prediction of the equation despite the presence of surface roughness and H 2 evolution. The advantages of this reactor in conducting diffusion controlled catalytic and electrochemical liquid–solid reactions and liquid–solid reactions involving sparingly soluble reactants that to be dispersed such as gases, solid particles and immiscible liquids were highlighted. [ABSTRACT FROM AUTHOR]