Studies on mass transfer on inner surface of an annular column with coaxially placed spiral coil as turbulent promoter was presented in this paper. The electrolyte is 0.01 M equimolal Potassium ferricyanide, Potassium Ferro cyanide and 0.5N sodium hydroxide. The variables covered in this study are the flow rate of the electrolyte, the geometric parameters of the promoter. The pitches of the coil covered in the study are 0.01 m, 0.02 and 0.03m. The diameter of the coil in the column is varied as 0.02 m, 0.03 m and 0.40 m. Reynolds number covered in the study ranges from 1000 to 15000. Enhancements in friction factors are 11 folds over the flow without promoter in the column. A model is developed in terms of geometric parameters and presented.