Flow pattern and model development for coaxially placed entry region coil-disc as turbulence promoter in circular conduit have been presented in this paper. The electrolyte was equimolal potassium ferricyanide, potassium ferrocyanide and excess sodium hydroxide. The mass transfer correlation is based on law of the wall similarity. The variables covered in this study are the flow rate of the electrolyte, the geometric parameters of the promoter – pitch of the coil from 0.015m to 0.035m, length of the coil 0.01m to 0.125m, disc diameter from 0.02m to 0.04m, height of the disc from 0m to 0.50m, velocity of the fluid from 0.0591m/s to 0.2751m/s. The correlation may be extended to a wider range of parameters by virtue of the law of the wall. Experimental mass transfer function in terms of geometric parameters have been developed and presented.g¯=5.76[Rem+]-0.003Pcd0.003Lcd0.001ddd0.616Hdd-0.00001