Effect of Triton-x-100 on the Rate of Hydrogen Evolution at a Cathode

The effect of H-2 evolution on the mass-transfer coefficient of cathode reduction of potassium ferricyanide at a mercury cathode was studied with the aim of (i) comparing the mass transfer behavior at a Hg cathode with that at solid electrodes under gas-evolving conditions and (ii) testing the effect of non-ionic surface-active agent on the mass transfer behavior of an H-2-evolving Hg cathode. It is found that the mass transfer coefficient at the Hg cathode was much higher than the value at a solid cathode. The mass transfer coefficient at H-2 evolving Hg was found to decrease in the presence of Triton-x-100 surfactant by an amount ranging from 62 to 82%, depending on the H-2 discharge rate and the Triton-x-100 concentrations.